Question

in a class of 49 students, number of girls is 2/5 of the boys. find the number of boys in the class.​

Answer 1

Answer:

Number of boys in a class is $35$.

Step-by-step explanation:

Given : Total number of students = $49$

           Number of girls in a class = $\frac{2}{5}$ of boys

To find : Number of boys in a class =?

Solution :

• It is given that, Total number of students = $49$

           Number of girls in a class = $\frac{2}{5}$ of boys

• Let, $x$ be the number of boys in a class.
• Now, according to given data, the equation becomes

      Number of girls + Number of boys = $49$

                               ∴  $\frac{2}{5}*x+x=49$

                                   ∴ $\frac{2x}{5}+x =49$

• By cross multiplication, we get

                                   ∴ $\frac{2x+5x}{5} =49$

• Transpose $5$ to other side, we get

                                    ∴ $7x=49*5$

                                     ∴ $7x=245$

                                     ∴ $x=\frac{245}{7}$

                                       ∴ $x=35$

• ∴ Number of boys in a class is $35$.