Question

in a class there are 40 students, tye number of girls is 3/5 of boys .Find the number of boys​

Answer 1

Answer :

• The number of boys in a class = 25.

Given :

• Number of total students in a class = 40.
• The number of girls is 3/5 of the number of boys.

To Find :

• The number of boys.

Solution :

Let,

The number of boys be x.

According to the question,

The number of girls is 3/5 of the number of boys.

So, the number of girls be x × 3/5.

Given,

Number of total students in a class is 40.

So,

=> Number of boys + Number of girls = Number of total students

=> x + x × 3/5 = 40

=> x + 3x/5 = 40

=> (x × 5) + 3x / 5 = 40

=> 5x + 3x / 5 = 40

=> 5x + 3x = 40 × 5

=> 8x = 200

=> x = 200/8

=> x = 25

Since, the value of x is 25.

That means,

Number of boys = x = 25.

Hence,

The number of boys in a class is 25.

Answer 2

Answer:

Correct Question :-

• In a class there are 40 students, the number of girls is 3/5 of boys. Find the number of boys.

Given :-

• In a class there are 40 students, the number of girls is 3/5 of boys.

To Find :-

• What are the numbers of boys in a class.

Solution :-

Let, the number of boys in a class be x

Now, it is given that :

Number of girls is 3/5 of boys, it means

$\mapsto$ $\sf Number\: of\: girls =\: \dfrac{3}{5} \times x$

According to the question,

↦ $\sf x + \dfrac{3}{5} \times x =\: 40$

↦ $\sf x + \dfrac{3x}{5} =\: 40$

↦ $\sf \dfrac{5x + 3x}{5} =\: 40$

↦ $\sf \dfrac{8x}{5} =\: 40$

By doing cross multiplication we get,

↦ $\sf 8x =\: 5(40)$

↦ $\sf 8x =\: 5 \times 40$

↦ $\sf 8x =\: 200$

↦ $\sf x =\: \dfrac{\cancel{200}}{\cancel{8}}$

➠ $\sf\bold{\green{x =\: 25}}$

Hence, the required numbers of boys are :

★ Number of boys :

⇒ $\sf x$

➲ $\sf\bold{\red{25}}$

$\therefore$ The numbers of boys in a class is 25.

VERIFICATION :-

↣ $\sf x + \dfrac{3}{5} \times x =\: 40$

↣ $\sf x + \dfrac{3x}{5} =\: 40$

By putting x = 25 we get,

↣ $\sf 25 + \dfrac{3(25)}{5} =\: 40$

↣ $\sf 25 + \dfrac{75}{5} =\: 40$

↣ $\sf \dfrac{125 + 75}{5} =\: 40$

↣ $\sf \dfrac{200}{5} =\: 40$

↣ $\sf 200 =\: 5(40)$

↣ $\sf 200 =\: 5 \times 40$

➦ $\sf\bold{200 =\: 200}$

Hence, Verified .