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Q:A:### Quick Answer

Thirty percent of 40 equals 12. This can be calculated by multiplying 30/100 x 40. It can also be found by multiplying 0.3 and 40. In both instances, the answer is 12.

Know MorePercentages are important in math and science. Often, percentage calculations must be completed from word problems. In this instance, the word "of" always indicates multiplication. For this problem, 30 percent of 40 equals 30/100 multiplied by 40.

The first step of percentage problems is to always convert the percentage to a decimal point or a fraction. In this instance, 30 percent can be converted into 30/100 or 0.3. Once the percentage has been converted, multiply the decimal or fraction by the whole amount to determine the final percentage.

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## What is 20 percent of 30?

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Full Answer >**Twenty percent of 30 is 6.**"Percent" means "per 100," or "divided by 100," so calculating 20 percent entails multiplying by 20 and dividing by 100, which is the same as multiplying by 0.20.Filed Under: - Q:
## What is percent elongation?

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Full Answer >**Percent elongation quantifies the ability of an element or compound to stretch up to its breaking point.**It is measured by dividing the change in length (up to the breaking point) by the original length, then multiplying by 100. Materials with a higher percentage elongation can stretch more before breaking.Filed Under: - Q:
## What is 25 percent of 100?

A:The product of 25 percent of 100 is 25. The best way to calculate percentages is to use what mathematicians call a proportion, which states that two ratios are equal to each other. All percentages can be converted into ratios using fractions in the following way: x % = x/100.

Full Answer >Filed Under: - Q:
## What is 20 percent of 80?

A:Twenty percent of 80 is 16. Percent refers to 1/100, so 20 percent is 20/100 and is written in decimal form as 0.20 or 0.2. To calculate 20 percent of 80, multiply 80 by 0.2, the answer of which is 16.

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