Question
Mathematics Question on Ratio and Proportion
A, B and C have 40, x and y balls, respectively. If B gives 20 balls to A, he is left with half as many balls as C. If together they had 60 more balls, each of them would have had 100 balls on an average. What is the ratio of x to y?
A
3 : 2
B
2 : 3
C
2 : 1
D
3 : 4
Answer
2 : 3
Explanation
Solution
If together they had 60 more balls, each of them would have had 100 balls on an average,
40+3X+Y+60=100
X+Y+100=300 ⇒ X+Y=200........(1)
If B gives 20 balls to A, he is left with half as many balls as C,
X−20=21Y
2X−40=Y(or)2X−Y=40.........(2)
Add equations (1) and (2)
3X=240(or)X=80
Substitute X value in equation (1)
80+Y=200(or)Y=20
X:Y=80:120(or)2:3
Hence, option B is the correct answer.The correct option is (B): 2 : 3