Answer:
Man's age = 40 +12 = 52
Sons's age = 14 + 12 = 26
Step-by-step explanation:
Man's age = 40
Sons's age = 14
Number of years = x
Father will be = 40 + x
Son will be = 14 + x
Twice the age of son after x years = father's age after x years
2(14+x)=40+x
28+2x=40+x
2x-x=40-28
x=12
After 12 years father will be twice as old as his son.
Check
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Man's age = 40 +12 = 52 (which is twice of 26)
Sons's age = 14 + 12 = 26