PSLE
Four girls, Kimberly, Elyse, Lucy and Roshel raised money for a charity. Kimberly and Elyse raised a total of $161. Together, Elyse, Lucy and Roshel raised a total of $277. The total amount of money raised by all 4 girls is 5 times the amount that Elyse raised. How much money did Lucy and Roshel raise?
Amount that Elyse and Kimberly raised = $161
Amount that Elyse, Lucy and Roshel raised = $277

Elyse is the repeated identity.

Elyse + Kimberly = 161 --- (1)
Elyse + Lucy + Roshel = 277 --- (2)

Amount that Elyse raised = 1 u
Amount that 4 girls raised = 5 u

(1) + (2)
(Elyse + Kimberly) + (Elyse + Lucy + Roshel) = 161 + 277
Elyse + 4 girls = 438
1 u + 5 u = 438
6 u = 438

1 u = 438 ÷ 6 = 73

Total amount that Lucy and Roshel raised
= 277 - 1 u
= 277 - 73
= $204

Answer(s): $204