PSLE A shop had a number of hi-fi systems for sale. After selling 20 of them in the morning and
17 of the remainder in the afternoon, it was left with
12 of the hi-fi systems. How many hi-fi systems were sold altogether?
Morning |
Remainder |
|
Afternoon |
Left |
20 |
1x1 |
6x1 |
1x6 |
1x6 |
5 u |
1 u |
6 u |
Fraction of the remainder left
= 1 -
17 =
67 6x17x1 Remainder =
1x62x6 Total
67 Remainder =
612 Total
Number of hi-fi systems sold in the morning
= 6 u - 1 u
= 5 u
5 u = 20
1 u = 20 ÷ 5 = 4
Number of hi-fi systems sold in the afternoon
= 1 u
= 1 x 4
= 4
Answer(s): 4