Question

every pupil in the class either swims or dances or does both.Three fifths of the class swim and three fifths dance.Five pupils both swim and dance.How many pupils are in the class?

Answer 1

Given:

Three fifths of the class swim.

Three fifths of the class dance.

Five pupils both swim and dance.

To find:

How many pupils are in the class?

Solution:

Let total number of pupils be x

So, no. of pupil that swim = (3/5)x = 3x/5

No. of pupil that dance = (3/5)x = 3x/5

5 students do both swim and dance.

Since, these 5 students are counted in both. So, we will subtract 5

So, the required equation is,

3x/5 + 3x/5 - 5 = x

6x/5 - 5 = x

6x - 25 = 5x

6x - 5x = 25

x = 25

Therefore, total number of pupils in the class are 25.

Answer 2

Answer:

Let the number of pupils be x. Then we get the equation:-

x = (3/5)x + (3/5)x

We know that we have 5 students as given. We will subtract that from the equation getting:-

x = (3/5)x + (3/5)x - 5

Now we start solving step-by-step.

x = (6/5)x - 5

x(1/5) = 5

x(0.2) = 5

x = 5/0.2

x = 25

THIS TELLS US THAT THE ANSWER IS 25.

I hope this helped you!