You can
put this solution on YOUR website!In three years, Alex will be 3 times as old as Precy.
A year ago, Alex was 7 times as old as Precy. How old are they now?
:
Let A and P = their present ages
:
Write an equation for each statement, simplify:
:
"In three years, Alex will be 3 times as old as Precy."
A+3 = 3(P+3)
A + 3 = 3P + 9
A = 3P + 9 - 3
A = 3P + 6
:
"A year ago, Alex was 7 times as old as Precy."
A-1 = 7(P-1)
A - 1 = 7P - 7
A = 7P - 7 + 1
A = 7p - 6
:
How old are they now?
:
Substitute (3P+6) for A in the above equation
3P + 6 = 7p - 6
6 + 6 = 7P - 3P
12 = 4P
P =
P = 3 yrs old Precy's present age
and
A = 3(3)+ 6
A = 15 yrs old is Alex's present age
;
:
Check the solution in the statement:
"A year ago, Alex was 7 times as old as Precy."
15 - 1 = 7(3-1)
