Question

Please answer the attached questions with proper solutions.

Answer 1

Step-by-step explanation:

Let the number of students be 100x

60% of the students are girls

=> number of girls = 60x

=> number of boys = 100x - 60x = 40x

40% of the students like maths

=> number of students liking math = 40x

20 boys join the school and they like math

=> new number of boys = 40x + 20

=> new number of students liking math = 40x + 20

new total number of students = 60x + 40x + 20 = 100x + 20

=> new percentage of girls = 60x / 100x + 20

According to the question, new percentage of girls = 58%

=> 60x / 100x + 20 = 58 / 100

=> 3x / (5x + 1) = 58 / 100

=> 300x = 58 (5x + 1)

=> 300x = 290x + 58

=> 10x = 58

new number of students liking math = 40x + 20

= 4(10x) + 20

= 4(58) + 20

= 232 + 20

= 252