In a class there are certain no of boys and girls If 15 girls are absent then no of boys will be twi...........

Logical Reasoning(Master ) Arithmetical Reasoning

In a class there are certain no. of boys and girls. If 15 girls are absent then no. of boys will be twice that of girls. If 45 boys are absent then girls strength will be 5 times that of boys. Find number of boys actually present ?

छोटे Courses बड़े Results

Master Arithmetical Reasoning

Prepare through Micro-courses

Try Now

Explanation:

15 girls are absent => b = 2(g-15)...... eqn...(1)
45 boys are absent => g - 15 = 5(b-45).....eqn...(2)
=> g = 5(b-45) + 15
=> b = 2((5(b-45)+15)-15)
=> b = 2(5b - 225 + 15 - 15)
=> b = 2(5b-225)
=> b = 10b - 450
=> 9b = 450
=> b = 50
so from equation(2)
g - 15 = 5(b - 45)
=> g - 15 = 5(50-45)
=> g - 15 = 5(5)
=> g = 25 + 15
=> g = 40
Therefore, the number of boys = 50 and girls = 40