Bob's age is now 3 times of Tom's age. Twelve years from now, tom will be 15 years old. How old is Bob now?

Question

please explain and show work

Answer 1

b = Bob's age now
t = Tom's age now
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age now is b = 3t
age in 12 years for t is t+12 = 15

Therefore, t now is 3 (that's 15-12 = 3)
b age now is 3*3 = 9

Answer 2

But if bob is 16 how old is tom

Answer 3

10