Question

Catherine's age is six more

than half of Sally's age. If the
sum of their ages equals 30,
how old is Catherine?

Answer 1

Sally is 16

Catherine is 14

Explanation:

Let s = Sally's age

Let c = Catherine's age

c = 1/2 s + 6

c + s = 30 Substitute in 1/2s + 6 for c

1/2s + 6 + s = 30 Combine like terms

1.5s + 6 = 30 Subtract 6 from both sides

1.5s + 6 - 6 = 30 - 6

1.5s = 24 Divide both sides by 1.5

`(1.5s)/(1.5)` =
`(24)/(1.5)`

s= 16 Sally is 16

c = 1/2s + 6

c = 1/2(16) + 6

c = 8 + 6

c = 14 Catherine is 14