Question 1097423
let H be Harvey's age and J be Jane's age, then
:
1)  H = 3 * J
2)  H + J = 48
:
use equation 1) and substitute for H in equation 2)
:
3 * J + J = 48
:
4J = 48
:
J = 12
:
H = 3 * 12 = 36
:
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Jane is 12 years old
Harvey is 36 years old
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