Question

in class of 40 pupils the number of girls is three-fifths of the number of boys .Find the number of boys in the class.​

Answer 1

Answer:

Step-by-step explanation:

Given :-

Total number of pupils in class = 40 

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

To Find :-

The number of boys in the class.​

Solution :-

Let the no.of boys in the class be x 

According to the question

Then no.of girls = 3x/5

Now , x + 3x/5 = 40 

⇒ (5x + 3x)/5 = 40 

⇒ 8x = 200

⇒ x = 200/8 

⇒ x = 25 

Hence, number of boys in the class is 25.

If we have to find the girls also, Then

Number of girls in the class = (3x/5)

= (3×25)/5 ( Because x = 25)

= 75/5

= 15 .

Hence, the number of girls in class is 15.

Verification :-

Number of girls + Number of boys = 40  

⇒ 15 + 25 = 40  

⇒ 40 = 40 .

Verified

Answer 2

Answer : Number of boys in the class is 25.

Step-by-step explanation:

Let the number of boys in the class be x.

∴ The number of girls in the class = 3x/5

The total number of pupils in the class = 40

According to the given condition,

(3x/5) + x = 40

⇒ 3x + 5x = 200 ...(Multiplying throughout by 5)

8x = 200

⇒ x = 200/8 ...(Transposing 8 to RHS)

x = 25

∴ The number of boys in the class is 25.

Additional information :

Now,

Number of girls in the class

= 3x/5

= 3*25/5

= 15

.°. The number of girls in the class is 15 .

Verification :

Total no. of pupils = 40

i.e. ,

No. of boys + No. of girls = 40

--» 25 + 15 = 40

--» 40 = 40

------------------------Hence, Verified....