In mathematics, a percentage is a way of expressing a number as a fraction of 100 (per cent meaning "per hundred" in French). It is often denoted using the percent sign, "%", or the abbreviation "pct". For example, 45% (read as "forty-five percent") is equal to 45 / 100, or 0.45. Let us see how to solve percent problem. - Source from Wikipedia
Formula – How to solve percent problem:
To solve the percent problem convert the fraction else a decimal to a percent and then multiply it by 100:
To get the percent value multiply the fraction into hundred. For example
` 2 / 4` (100) = `2 / 4 ` * 100 = 0.5 * 100 = 50%
To convert the percent value to fraction divide it by hundred.
25% = `25 / 100 ` = `1 / 4`
Example: How to solve percent problem:
Problem 1:
What is the decimal value of 72%?
Solution:
To obtain the decimal value we have to divide the given number by 100. Which is `72 / 100` = 0.72.
Therefore the decimal value of 72% is 0.72.
Problem 2:
What is the decimal value of 86.3%?
Solution:
To obtain the decimal value we have to divide the given number by 100. Which is `(86.3) / 100` = 0.863.
Therefore the decimal value of 86.3% is 0.863.
Problem 3:
What is the decimal value 18% of 60?
Solution:
To find 18 percentages divide 18 by 100 and then multiply it by 60.
= `18 / 100` * 60 = 10.8
Hence 18% of 60 = 10.8
Problem 4:
What is the decimal value for 15.5% of 150?
Solution:
To find 15.5 percent divide 15.5 by 100 and then multiply it by 150.
=` (15.5) / 100` * 150 = 23.25
Hence 15.5% of 150 = 23.25
Problem 5:
The book cost is 5.00 dollars. Now it was 15% increased. What will be the new cost?
Solution:
Multiply the cost by 15%. That is `15 / 100` * 5.00.
= `15 / 100` * 5.00 = 0.75
Add this decimal value with original cost (5.00+0.75= 5.75)
Therefore the original cost of the book is 5.75 dollars.
Problem 6:
In a box there are 85 chocolates. Suppose if a boy took out 60% of chocolates, how many chocolates did he left in the box?
Solution:
The boy took out the chocolates from the box is 60% of 85 or else 60 / 100 × 85
`60 / 100` × 85 = 51%
So the box has 85 chocolates and the boy took out 51 chocolates. Hence the number of chocolates the boy left in the box is 85 – 51 = 34.
Therefore the boy left 34 chocolates in the box.
Problem 7:
A theatre contains 530 chairs. 470 of them are occupied. What percentages of the chairs not occupied?
Solution:
Number of chairs = 530
Number of chairs occupied = 470
Number of chairs not occupied = 530 – 470 = 60
Number of chairs not occupied percentage = `60 / 530` × 100 = 11.32%
Practice problems – How to solve percent problem:
Problem 1:
What is the decimal value of 27%?
Solution:
27% = 0.27
Problem 2:
What is the decimal value 8% of 75?
Solution:
8% of 75 = 6
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