PSLE
Four girls, Erika, Zara, Winnie and Esther raised money for a charity. Erika and Zara raised a total of $98. Together, Zara, Winnie and Esther raised a total of $178. The total amount of money raised by all 4 girls is 5 times the amount that Zara raised. How much money did Zara raise?
Amount that Zara and Erika raised = $98
Amount that Zara, Winnie and Esther raised = $178

Zara is the repeated identity.

Zara + Erika = 98 --- (1)
Zara + Winnie + Esther = 178 --- (2)

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

(1) + (2)
(Zara + Erika) + (Zara + Winnie + Esther) = 98 + 178
Zara + 4 girls = 276
1 u + 5 u = 276
6 u = 276

1 u = 276 ÷ 6 = 46

Amount that Zara raised
= 1 u
= $46

Answer(s): $46