Question 545562
let t = teacher's age now
let s = sister's age
:
"This year she is three times as old as her little sister."
t = 3s
:
"However, six years ago she was five times as old as her sister."
t -6 = 5(s - 6)
t - 6 = 5s - 30
t = 5s - 30 + 6
t = 5s - 24
From the 1st statement, replace t with 3s
3s = 5s - 24
24 = 5s - 3s
24 = 2s
s = 24/2
s = 12 yr is sisters present age
then
3(12) = 36 yrs is teacher's age
:
:
Check solution in the statement:
"six years ago she was five times as old as her sister."
36 - 6 = 5(12 - 6)
30 = 5(6); confirms our solution