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Q: A: ### Quick Answer

**Figuring percentages is determining how many of something is per 100.** For example, 50 percent is the same as 50 per 100.

To determine the number when giving the percentage, the formula "percent / 100 x the number" is used. For instance, to determine 50 percent of 80, users would divide 50 by 100 and multiply the answer by 80. Written out it is 50 / 100 x 80 = 40, so 50 percent of 80 is 40.

To determine the percentage of something, users should first set up a fraction. For example, if 30 of the 300 people showed up for the event, what is the percentage of people that came? To calculate this, users should first divide 30 by 300 and then multiply the answer by 100. Written out as a formula, it should appear as 30 / 300 x 100 = 10. So 10 percent of the people that were invited came to the event.

Commonly, stores use percentages to reflect sale prices. For instance, a store is holding a sale for 33 percent off an item. If the item is $200, users should determine the price after the discount. This is done by taking the percentage off and dividing it by 100. It is then multiplied by the price of the item and finally, deducted from the price. The formula is 33 / 100 x 200 = 66. 200 – 66 = 134. The final price of the item after the discount is $134.

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## How do you average your grades?

A:

Full Answer >**To calculate an average grade, first add up all the individual grades, then divide by the total number of grades.**Letter grades or percentage grades can be converted to the 4.0 scale to find the grade point average, or GPA.Filed Under: - Q:
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A:Standard deviation is a measure of the variation or diversity of scores in a set of data. It is used to determine how much data varies from the average of a population. The larger the deviation, the more spread out the data set. Standard deviation is represented by the Greek letter sigma.

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## What is the difference between explanatory variables and response variables?

A:A response variable measures an outcome of a study. It is the particular quantity about which questions are asked. An explanatory variable is any factor that can influence the response variable. An explanatory variable attempts to explain the observed outcomes. The response variable is usually called dependent, while the explanatory variable is sometimes called independent.

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## How many babies are born each year?

A:

Full Answer >**According to UNICEF article updated in May 2012, about 130 million babies are born each year.**CNN notes that an accurate count of the worldwide birth rate is difficult since many countries don't register all new births.Filed Under: