Question

Tom is 4 more than twice Andrews age. Sara is 8 less than 5 times Andrews age. If Tom and Sara are twins, how old is Andrew? Show your work

Answer 1

T = 4 + 2A
S = 5A - 8
T = S
Since T and S are equal, set them against each other
2A + 4 = 5A - 8
Subtract 2A from each side, and add 8 to each side
12 = 3A
Divide each side by 3
A = 4
So Andrew is 4 years old
If Andrew is 4, then Tom is twice that plus 4, or 12. Sarah is 5 times 4 less 8, or 12.