Question

the number of girls enrolled in a village school providing free elementary education has doubled this year taking the previous enrollment as x and the current enrollment y form a linear equation in two variables write the equation in standard form how many girls were enrolled previous year if the present enrollment is 30

Answer 1

let,
  x = previous enrollment
  y = current enrollment.

         therefore:
                 
                 y = 2x

now, is y = 30

then,

       y = 2x

       30 = 2x

       x = 30/2 = 15

the number of girls enrolled previous year was 15.

Answer 2

question was not so hard