PSLE
Tammy had rubik's cubes for sale. In the morning, she sold ³₈ of the rubik's cubes. In the afternoon, she sold ²₅ of the remaining rubik's cubes. After that, there were 60 rubik's cubes left. How many rubik's cubes did Tammy have at first?
Fraction of rubik's cubes left after selling in the morning
= 1 - ³₈
= ⁵₈

Fraction of the remaining rubik's cubes after selling in the afternoon
= 1 - ²₅
= ³₅

³₅ of remaining rubik's cubes = 60
¹₅ of remaining rubik's cubes = 60 ÷ 3 = 20
⁵₅ of remaining rubik's cubes = 5 x 20 = 100

⁵₈ of total rubik's cubes = 100
³₈ of the total rubik's cubes = 100 ÷ 5 = 20
⁸₈ of the total rubik's cubes = 8 x 20 = 160

Number of rubik's cubes at first = 160

Answer(s): 160