The sum of the number of boys and girls in a school is 150.  If the no. of boys is x, the number of girls becomes x% of the total number of students.  The number of boys is?

90 50 40 60

60

Boys + Girls = Total no. of students x + x% × 150 = 150 x + \(\frac{x × 150 }{100}\) = 150 100x + 150x = 15000 250x = 15000 x =  \(\frac{15000}{250}\) = 60