In which subjects is the difference between the number of boys an
Directions: In a University, there are 1200 students studying four different subjects, Mathematics, Statistics, Physics and Chemistry. 20% of the total number of students are studying Mathematics, one-fourth of the total number of students are studying Physics, 320 students are studying Statistics. Three-fifth of the total number of students studying Chemistry are girls. 150 boys are studying Mathematics. 60% of the students studying Physics are boys. 250 girls are studying Statistics.
Question 1: In which subjects is the difference between the number of boys and girls is equal?
A. Mathematics and Chemistry
B. Statistics and Chemistry
C. Mathematics and Physics
D. Mathematics and Statistics
Right Answer is: C
SOLUTION
Mathematics:
Total number of students = 240 [From previous question]
Number of boys = 150
Number of girls = 240 – 150 = 90
Difference between number of boys and girls = 150 – 90 = 60
Chemistry:
Total number of students = 340
Number of girls = 3/5 × Total = 3/5 × 340 = 204
Number of boys = 340 – 204 = 136
Difference = 204 – 136 = 68 students
Statistics:
Total number of students = 320
Number of girls = 250
Number of boys = 320 – 250 = 70
Difference = 250 – 70 = 180
Physics:
Total number of students = 300
Number of boys = 60/100 × 300 = 180
Number of girls = 300 – 180 = 120
Difference = 180 – 120 = 60
∴ Difference is same (60) for Mathematics and Physics