SOLUTION: 20% of the total number of pupils in a class is 6.How many pupils are there in the class altogether?

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Question 1044563: 20% of the total number of pupils in a class is 6.How many pupils are there in the class altogether?

Answer by ikleyn(52835) About Me  (Show Source):
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20% of the total number of pupils in a class is 6.How many pupils are there in the class altogether?
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Solution 1

20% is 1%2F5: 20%2F100 = 1%2F5.

So, 1%2F5 of the total number of pupils in the class is 6.
Then the total number of pupils in the class is 5 times 6: 5*6 = 30.

Answer.  There are 30 pupils in the class.


Solution 2

Let x be the total number of pupils in the class.

Then you are given that %2820%2F100%29%2Ax = 6.

Cancel the factor 20 in the numerator and the denominator in the left side.

You will get  %281%2F5%29%2Ax = 6.

Multiply by 5 both sides. You will get x = 5*6 = 30.

The same answer.

On percentage read the lessons in this site
    - Percentage problems
    - Percentage word problems (Type 1 problems, Finding the Part)
    - Percentage word problems (Type 2 problems, Finding the Rate)
    - Percentage word problems (Type 3 problems, Finding the Base)
    - More complicated percentage problems
in this site.