in 10 years , a will be twice as old as b was 10 years ago . if a is now 5 years older than b the present age of b is
n0 = 10.0
n1 = 10.0
n2 = 5.0
t0 = n0 * 2.0
t1 = n0 + t0
answer = n2 + t1
print(answer)