SOLUTION: Dick is now seven times as old as Harry. In six years Dick will be five times as old as Harry. How old will Harry be in 5 years?
Algebra ->
Expressions-with-variables
-> SOLUTION: Dick is now seven times as old as Harry. In six years Dick will be five times as old as Harry. How old will Harry be in 5 years?
Log On
You can put this solution on YOUR website! Write an equation for each statement:
Let d = Dicks present age
Let h = Harry's present age
:
Dick is now seven times as old as Harry.
d = 7h
:
In six years their ages are:
(d+6) and (h+6)
:
In six years Dick will be five times as old as Harry.
(d+6) = 5(h+6)
d + 6 = 5h + 30
d = 5h + 30 - 6
d = 5h + 24
:
How old will Harry be in 5 years?
First, find h's present age by substituting 7h for d in the above equation
7h = 5h + 24
7h - 5h = 24
2h = 24
h = 24/2
h = 12 is Harry's present age
:
In five years he will be 17, obviously
:
:
Check our solution of h = 12 and d = 7*12 = 84 in the statement:
"In six years Dick will be five times as old as Harry."
84 + 6 = 5(12 + 6)
90 = 5(18); confirms our solutions
