Question 964285
.
x=how many years
37yrs+x=2(10yrs+x)
37yrs+x=20yrs+2x Subtract 20 yrs from each side.
17yrs+x=2x Subtract x from each side.
17 yrs=x 
ANSWER: The mother will be twice as old as the son in 17 yrs.
CHECK:
37yrs+17yrs=2(10yrs+17yrs)
54yrs=2(27yrs)
54yrs=54yrs