Want to Know it? Answers to life’s questions

How do you calculate percentages

March 11th, 2010 at 07:27am Under math

In math, a percentage is a way of writing a number as a fraction of 100 (per cent means per hundred). For example, if you hear that 40% of people own a pet this means that 40 out of 100 people own a pet. Many people ask ‘how do you calculate percentages’? This post will answer that question and give you a few examples to help you along.

How do you calculate percentage

Example 1: Converting Decimals

Many basic percentage problem require you to convert a decimal to a percentage. To do this, simply multiply the decimal by 100. This moves the decimal point two places to the right. Here are two examples of how to do this…

Question:

Convert 0.45 to a percentage

Answer:

Multiply 0.45 by 100 (0.45 x 100)

The answer is 45 (move the decimal place to the right 2 places). Therefore, 0.45 is 45%.

Question:

Convert 0.657 to a percentage

Answer

0.657 x 100 = 65.7 (moving the decimal point to the right 2 places)

Therefore, 0.657 is 65.7%

Example 2: What percentage of…

This is best illustrated by a couple of examples.

Question:

In a park, Bob observed that 20 out of 50 dogs have brown hair. What percentage of dogs had brown hair?

Answer:

First, divide 20 by 50: 20/50 = 2/5 = 0.40

Next, multiply the answer by 100 (remember, just move the decimal point two places to the right).

0.40 x 100 = 40

Therefore, the answer is 40%

Question:

Bob was sitting by the road one day and observed that 30 out of 120 cars were black. Find the percentage of cars that were NOT black.

Answer:

You want the cars that were not black. If 30 out of 120 cars were black, how many cars were not black?

Well, 120 – 30 = 90.

Therefore, 90 out of 120 cars are not black.

First, do 90/120 = 9/12 = 3/4 = 0.75

0.75 x 100 = 75

So 75% of the cars were not black.

Example 3: Percentage Increases

Again, I will illustrate by example.

Question:

The price of a $2.00 soft drink was increased to $2.40. Find the percentage increase.

Answer:

First, find the difference in price:

2.40 – 2.00 = 0.40

Next, divide 0.40 by 2.00

0.40/2.00 = 1/5 = 0.20

Now, convert the decimal to a percentage by multiplying by 100.

0.20 x 100 = 20 (move the decimal 2 places to the right!)

Therefore, the price has increased by 20%.

Other Maths Topics:

How do you find the median

Basic algebra problems

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Where Do Olive Trees Grow

March 11th, 2010 at 05:23am Under where do

The olive tree is an evergreen tree that produces fruit that bears the same name (olives). It is a short, yet stout, tree that does not commonly grow past 15m trall. The olive tree has been a significant plant within Mediterranean culture and history and is listed in many historical texts such as the bible. But, where do olive trees grow? This article will answer this question and take a look at some interesting facts about olives.

Where do olive trees grow?

Olive trees are native to the Mediterranean, Asia and Africa. It is believed that the tree originated in the Mediterranean region and spread to the surrounding areas from here. There is evidence that the olive tree has been cultivated for about 9000 years.

Today the olive tree has been introduced into many countries of the world, but it is still mainly grown in Mediterranean countries. The largest worldwide producers of olives are Spain, Italy, Greece, Turkey and Tunisia.

Interesting facts about olives

• An olive tree can live for over 3000 years and there are some olive trees in the world that are believed to be over 4000 years old!
• Canned black olives may actually be green olives that have added chemical to make them black.
• The main use for the olive is the popular and healthy olive oil. This is made by grinding and pressing the olives.
• There are six natural subspecies of olives around the world.
• An olive tree can actually be considered a pest! In South Australia the introduced olive tree has become a major weed.
• The olive tree is quite hardy, but there are some natural predators (like rabbits) and diseases (fungi and bacteria) that can cause problems to plantations.

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How do you get kidney stones

March 11th, 2010 at 04:30am Under Health

A kidney stone is a build up of dissolved urinary minerals that forms crystal aggregations. These usually pass through the body without causing any problems or symptoms, but if the stones becomes large enough they can start to cause problems. But, how do you get kidney stones? This article will answer this question and take a look at the symptoms of this condition.

How do you get kidney stones?

There are two main types of kidney stones. The first type of stone is comprised of calcium oxalate crystals and makes up 80% of cases. This type of kidney stone was thought to be caused by high calcium diets, but it has since been shown that a low calcium diet puts you higher at risk of this type of kidney stone.

The second most common type of kidney stone is made up of uric acid. These type of stones account for about 5-10% of cases. This is generally caused by excessive amounts of uric acid in the urine.
Other types of kidney stones are less common and can be caused by urea-splitting bacteria or other specific illness or diseases.

What are the symptoms of kidney stones?

Most kidney stones cause no problems at all, but when a stone grows in size it can cause the following symptoms;

• A strong, gripping pain in the back (just below the ribs) that may reach around the front and down to the groin.
• Nausea and vomiting.
• Blood or pus in the urine.
• Visible stones passing out like gravel, (usually caused by uric acid stones).
• Urgency to urinate.
• Reduced urinary volume because of a blockage.

Kidney stones can be detected via x-ray, ultrasound or CT scan and your doctor may request a blood test and/or urine sample to help prevent them in the future. It is important to keep any stones that you pass so that they can be examined and analyzed.

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Uses of Hydrogen

March 10th, 2010 at 11:54pm Under uses

Hydrogen is a chemical element with the atomic number 1. It is usually placed in the top left corner of the periodic table. Many people ask me ‘what are some of the common uses of hydrogen’? This post will answer that question. Note that I also gave some of the basic uses of hydrogen in the post ‘Who Discovered Hydrogen‘.

Uses of Hydrogen

• Used to process (‘upgrade’) fossil fuels.
• Used to produce ammonia- used in common household cleaning products.
• Hydrogen is used as a hydrogenating agent to produce methanol and convert unhealthy unsaturated fats and oils to saturated fats and oils.
• The triple point of hydrogen (the temperature where all 3 phases- gas, solid and liquid- are in equilibrium) can be used to calibrate some thermometers.
• Tritium, a radioactive isotope of hydrogen, is produced in nuclear reactions. It can be used to make hydrogen bombs and acts as a radiation source in luminous paints. In the biosciences, tritium is sometimes used as an isotopic label.
• Hydrogen (either used on its own or combined with nitrogen) is used in many manufacturing plants to determine whether there are any leaks. It is also used to detect leaks in food packages.
• Hydrogen is used as a rotor coolant in electrical generators.
• Hydrogen gas is used as a shielding gas in atomic hydrogen welding (AHW).
• Used in the production of hydrochloric acid- used widely in chemical industries.
• Hydrogen gas is used to reduce many metallic ores.
• Can be used to make water.

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When Does Your Third Trimester Start

March 10th, 2010 at 07:26am Under Health+ pregnancy

Pregnancy is divided into three trimesters even though the duration of a pregnancy is usually referred to in a weekly time scale. The trimesters are useful for breaking the pregnancy up into developmental stages. During the third trimester the majority of the weight gain takes place and the fetus is growing rapidly during this period. This is also the trimester in which labor and birth actually takes place. But you might still be wondering – when does your third trimester start? This article will answer that question and discuss the symptoms and development that takes place during this period.

When does your third trimester start?

The third trimester starts at 28 weeks and continues until the birth of your baby. This is the seventh month of your pregnancy and during this time the fetus grows larger and the organs begin to mature. You will probably find that the fetus moves frequently during this period and this can be very disruptive. The fetus begins to prepare for birth with improvements in brain, eye, and muscle function. Your due date is the end of the 40th week of pregnancy, however, a full-term pregnancy can happen between the 37th and 42nd weeks of pregnancy and is considered perfectly normal.

Third trimester symptoms

• The navel (belly button) may pop out
• Back and muscle (especially pelvic and hip) aches
• Rapid weight gain
• Heart Burn
• Fatigue
• Braxton Hicks contractions (false labor)
• Constipation and haemorrhoids
• Fluid builds up causing swelling (especially in the ankles)
• Frequent urination
• Difficulty sleeping as the fetus makes more forceful movements.

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What Does am and pm Stand for

March 10th, 2010 at 06:51am Under facts

Unless you are use military time then you will be using the 12 hour clock that was believed to be developed sometime before 1500 BC in Egypt or Mesopotamia. The 24 hour day is broken up into two lots of 12 hours am and pm. Today the terms am and pm are used in English speaking countries, but the 12 hour clock is used in almost every country in some manner. But, what does am an pm stand for? This article will answer this question and take a look at interesting facts about the 12 hour clock.

What does am and pm stand for?

Many people think that am and pm stand for “after midnight” and “prior to midnight,” but this is actually false. The abbreviation am stands for ante meridiem which is Latin for “before mid day” and pm stands for post meridiem which is Latin for “after mid day.” This translates into the English form of “before noon” and “afternoon.”

Other interesting facts about the 12 hour clock

• An Egyptian sundial and water clock that were separated into 12 hour segments dating to 1500 BC have been found in a Pharaohs tomb. The Romans also used a 12 hour clock.
• The 12 hour dial became popular with mechanical clocks during the 15th and 16th centuries and this has continued to this day.
• The abbreviations for am and pm are often also written as a.m. and p.m. or AM and PM.

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Where do the New England Patriots Play

March 10th, 2010 at 05:12am Under where do

The New England Patriots (often called the ‘Pats’) play in the AFC East as part of the National Football League (NFL). But where do the New England Patriots play? This post will answer that question and then tell you a few interesting facts about the Patriots.

Where do the New England Patriots Play?

The Patriots play at Gillette Stadium, located 21 miles southwest of downtown Boston. The address of Gillette Stadium is 1 Patriot Place, Foxborough, Massachusetts. The stadium was originally called CMGI Field before Gillette purchased the naming rights of the stadium after the ‘dot com’ bust. The stadium is accessible by rail on the Providence/Stoughton and Franklin lines only when an event (other than soccer) takes place at the stadium.

Interesting Facts about the New England Patriots

• The Patriots are one of only two teams in the history of the NFL to win three Super Bowls in four years. The Dallas Cowboys are the other.
• When the NFL and AFL merged in 1970, the Patriots were placed in the AFC East Division where they still play to this day.
• In 2007, the Patriots became on the fifth team to go undefeated in the regular season. Unfortunately, they lost the Super Bowl to the New York Giants (17-14).
• The team was originally known as the Boston Patriots until they relocated to Foxborough in 1971.

Related Topics

Where do the Carolina Panthers Play

Where do the Washington Redskins Play

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Jeff Bridges Movie List

March 9th, 2010 at 03:55am Under list

Jeff Bridges is a Hollywood actor and producer that has been involved in many movies over his career. Even though he was first nominated for an Oscar in 1972 it took until 2010 before he actually won one for his lead role in the movie Crazy Heart! The following is a list of the movies that Jeff Bridges has been involved in over his long career.

Actor

True Grit (2010) (pre-production) as Marshal Reuben J. Cogburn
Tron Legacy (2010) (post-production) as Kevin Flynn
Crazy Heart (2009) as Bad Blake
The Men Who Stare at Goats (2009) as Bill Django
A Dog Year (2009) as Jon Katz
The Open Road (2009) as Kyle
How to Lose Friends & Alienate People (2008) as Clayton Harding
Iron Man (2008) as Obadiah Stane
Surf’s Up (2007) (voice) as Zeke ‘Big Z’ Topanga / ‘Geek’
Stick It (2006) as Burt Vickerman
Tideland (2005) as Noah
The Moguls (2005) as Andy Sargentee
The Door in the Floor (2004) as Ted Cole
Seabiscuit (2003) as Charles Howard
Masked and Anonymous (2003) as Tom Friend
K-PAX (2001) as Dr. Mark Powell
Scenes of the Crime (2001) as Jimmy Berg
The Contender (2000) as President Jackson Evans
Simpatico (1999) as Lyle Carter
The Muse (1999) as Jack Warrick
Arlington Road (1999) as Michael Faraday
The Big Lebowski (1998) as Jeffrey Lebowski – The Dude
Hidden in America (1996) (TV) as Vincent
The Mirror Has Two Faces (1996) as Gregory Larkin
White Squall (1996) as Captain Christopher ‘Skipper’ Sheldon
Wild Bill (1995) as James Butler ‘Wild Bill’ Hickok
Blown Away (1994) as James ‘Jimmy’ Dove/Liam McGivney
Fearless (1993) as Max Klein
The Vanishing (1993) as Barney Cousins
American Heart (1992) as Jack Kelson
The Fisher King (1991) as Jack Lucas
Texasville (1990) as Duane Jackson
The Fabulous Baker Boys (1989) as Jack Baker
Cold Feet (1989) (uncredited) as Bartender
See You in the Morning (1989) as Larry Livingstone
Tucker: The Man and His Dream (1988) as Preston Tucker
Nadine (1987) as Vernon Hightower
The Morning After (1986) as Turner Kendall
The Thanksgiving Promise (1986) (TV) (uncredited) as Neighbor
8 Million Ways to Die (1986) as Matthew ‘Matt’ Scudder
Jagged Edge (1985) as Jack Forrester
Starman (1984) as Starman
Against All Odds (1984) as Terry Brogan
Kiss Me Goodbye (1982) as Rupert
The Last Unicorn (1982) (voice) as Prince Lir
TRON (1982) as Kevin Flynn / Clu
The Girls in Their Summer Dresses and Other Stories by Irwin Shaw (1981) (TV) as Michael Loomis
Cutter’s Way (1981) as Richard Bone
Heaven’s Gate (1980) as John L. Bridges
The American Success Company (1980) as Harry
Winter Kills (1979) as Nick Kegan
Somebody Killed Her Husband (1978) as Jerry Green
King Kong (1976) as Jack Prescott
Stay Hungry (1976) as Craig Blake
Hearts of the West (1975) as Lewis Tater
Rancho Deluxe (1975) as Jack McKee
Thunderbolt and Lightfoot (1974) as Lightfoot
The Iceman Cometh (1973) as Don Parritt
The Last American Hero (1973) as Elroy Jackson Jr./Junior Jackson
Lolly-Madonna XXX (1973) as Zack Feather
Bad Company (1972) as Jake Rumsey
Fat City (1972) as Ernie
The Last Picture Show (1971) as Duane Jackson
In Search of America (1971) (TV) as Mike Olson
Halls of Anger (1970) as Doug
The Yin and the Yang of Mr. Go (1970) as Nero Finnegan
Silent Night, Lonely Night (1969) (TV) as Young John
The Company She Keeps (1951) (uncredited) as infant at the train station

Producer

Crazy Heart (2009) (executive producer)
Hidden in America (1996) (TV) (executive producer)
American Heart (1992) (producer)

Other Oscar Winners
Tom Hanks Movie List

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Where Do Bananas Come From

March 9th, 2010 at 03:41am Under food+ where do

The banana is a tropical fruit that has been cultivated for human consumption for thousands of years. It is a popular and healthy fruit that is available in both desert (the common yellow types of banana) and green cooking bananas. But, where do bananas come from? This article will answer that question and take a look at some of the other interesting facts about bananas.

Where do bananas come from?

Bananas have been domesticated for thousands of years and are native to south-east Asia. Recent evidence suggests they were first domesticated in Papua New Guinea sometime around 5000-8000 BC. This was followed by a separate domestication in other parts of South East Asia. There is also evidence of domestication in Africa dating from about the 6th century.

Today, wild bananas can be found in New Guinea, Indonesia, Malaysia and the Philippines. Domestic banana growing now extends to over 107 countries with the top producers being India, China, Philippines, Brazil, Ecuador and Indonesia. Each year there are about 73 million metric tons of bananas produced all around the world.

Interesting facts about bananas

• Most of us know that ripe bananas are yellow, but they also come in purple and red.
• People with a latex allergy may also be allergic to bananas.
• Bananas are considered to be very healthy and contain good levels of vitamin B6, vitamin C, and potassium.
• The original wild bananas contained large seeds.
• Today bananas are picked when they are green and unripe. They are then stored and exposed to ethylene gas to assist in the ripening process. They have a different taste to the tree ripened fruit.

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How do you find the median

March 9th, 2010 at 12:12am Under math

If you have done statistics in math you may have come across the term ‘median’. But what is the median? How do you calculate the median? This post will tell you how to find the median through a step-by-step process. There are 2 examples at the bottom of the post.

What is the median?

The median is simply the middle score. It is used to separate the ’scores’ into two halves.

How do you find the median

The process of finding the median changes depending on whether you have an odd or even number of values.

For an odd number of values

1. Sort the scores from lowest to highest.
2. Determine which is the middle score. There should be an equal number of scores on either side of the median. For example, if you have 5 scores the 3rd score will be the middle value. There will be 2 scores on either side of the median.
3. The middle score is the median!

For an even number of values

1. Sort the scores from lowest to highest.
2. Determine the 2 middle scores. There should be an equal number of scores on either side of the median. For example, if you have 6 scores the 3rd and 4th will be the ‘middle scores’. There will be 2 scores on either side of the median.
3. Find the average of the 2 middle scores. This is calculated by adding the values and then dividing the answer by 2.
4. The average is the median!

Examples

For an Odd Number of Scores

If you have the numbers 4, 8, 5, 9, 2, 10, 7

Arrange in order: 2, 4, 5, 7, 8, 9, 10

The middle score (the median) is 7. There are 3 scores on either side (2, 4, 5 on the left and 8, 9, 10 on the right)

For an Even Number of Scores

If you have the numbers 4, 8, 5, 9, 2, 10, 7, 13

Arrange in order: 2, 4, 5, 7, 8, 9, 10, 13

The middle scores are 7 and 8. There are 3 scores on either side (2, 4, 5 on the left and 9, 10, 13 on the right).

The average of the middle scores is (7+8)/2. The answer is 7.5.

Therefore, the median is 7.5

Other Math Topics

Basic Algebra Problems

Fifth Grade Math Problems

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