PSLE
Gillian had mini-helicopters for sale. In the morning, she sold ⁵₈ of the mini-helicopters. In the afternoon, she sold ⁴₇ of the remaining mini-helicopters. After that, there were 45 mini-helicopters left. How many mini-helicopters did Gillian have at first?
Fraction of mini-helicopters left after selling in the morning
= 1 - ⁵₈
= ³₈

Fraction of the remaining mini-helicopters after selling in the afternoon
= 1 - ⁴₇
= ³₇

³₇ of remaining mini-helicopters = 45
¹₇ of remaining mini-helicopters = 45 ÷ 3 = 15
⁷₇ of remaining mini-helicopters = 7 x 15 = 105

³₈ of total mini-helicopters = 105
⁵₈ of the total mini-helicopters = 105 ÷ 3 = 35
⁸₈ of the total mini-helicopters = 8 x 35 = 280

Number of mini-helicopters at first = 280

Answer(s): 280