Question

Bob's age is 15 years less than half his father's age. In six years his father's age will be eleven years more than triple Bob's age. What is his father's age now

Answer 1

Answer: the father is 44 years old now

Step-by-step explanation:

Let Bob's present age be represented by x

Let his father's present age be represented by y

Bob's age is 15 years less than half his father's age. This means that

x = y/2 - 15

x + 15 = y/2

y = 2x + 30

y - 2x = 30 - - - - - - - - - -1

In six years his father's age will be eleven years more than triple Bob's age. This means that

y + 6 = 3(x + 6) + 11

y + 6 = 3x + 18 + 11

y - 3x = 18 + 11 - 6

y - 3x = 18 + 11 - 6

y - 3x = 23 - - - - - - - - -2

Subtracting equation 2 from equation 1, it becomes

x = 7

y = 2x + 30

y = 2×7 + 30

y = 14 + 30

y = 44