Abrar

A father is 4 times as old as his son. 5 years ago the sum of their age was 70. Find their present age.

Wrong! The answer has to be 7 m/s. Its just reverse logic. M1Vc + M2Vc = M1V1 + M2V2. Vc = 2, V1 = 0 (assuming it starts from rest), V2 = unknown, and thats what you are finding.

M1 = 75, M2 = 30

I want to this answer

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