PSLE
Xuan spent ¹₇ of her money on a blouse and 4 sweaters. The blouse cost 2 times as much as each sweater. Xuan spent ²₅ of her remaining money on a necklace. She spent $166.4 more on the necklace than on the 4 sweaters.
(a) What fraction of Xuan's money was spent on each sweater?
(b) How much money did Xuan have at first?
(a)
Cost of 1 sweater = 1 u

Cost of 4 sweaters
= 4 x 1 u
= 4 u

Cost of 1 blouse = 2 u

Cost of 1 blouse and 4 sweaters
= 2 u + 4 u
= 6 u

Fraction of Xuan's money spent on each sweater
= ¹₆ x ¹₇
= ¹₄₂

(b)
¹₇ of her money = 6 u
⁶₇ of her money = 6 x 6 u = 36 u

Xuan's remaining money = 36 u

Cost of the necklace
= ²₅ x 36 u
= 14.4 u

Amount that Xuan spent more on the necklace than on the 4 sweaters
= 14.4 u - 4 u
= 10.4 u

10.4 u = 166.4

1 u = 166.4 ÷ 10.4 = 16

⁷₇ of her money = 7 x 6 u = 42 u

Amount that Xuan had at first
= 42 u
= 42 x 16
= $672

Answer(s): (a) ¹₄₂ ; (b) $672