PSLE
Four girls, Nora, Kylie, Usha and Joelle raised money for a charity. Nora and Kylie raised a total of $168. Together, Kylie, Usha and Joelle raised a total of $420. The total amount of money raised by all 4 girls is 5 times the amount that Kylie raised. How much money did Nora raise?
Amount that Kylie and Nora raised = $168
Amount that Kylie, Usha and Joelle raised = $420

Kylie is the repeated identity.

Kylie + Nora = 168 --- (1)
Kylie + Usha + Joelle = 420 --- (2)

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

(1) + (2)
(Kylie + Nora) + (Kylie + Usha + Joelle) = 168 + 420
Kylie + 4 girls = 588
1 u + 5 u = 588
6 u = 588

1 u = 588 ÷ 6 = 98

Amount that Nora raised
= 168 - 1 u
= 168 - 98
= $70

Answer(s): $70