PSLE A shop had a number of hi-fi systems for sale. After selling 30 of them in the morning and
13 of the remainder in the afternoon, it was left with
13 of the hi-fi systems. How many hi-fi systems were left?
Morning |
Remainder |
|
Afternoon |
Left |
30 |
1x1 |
2x1 |
2x2 |
1x2 |
3 u |
1 u |
2 u |
Fraction of the remainder left
= 1 -
13 =
23 2x13x1 Remainder =
1x23x2 Total
23 Remainder =
26 Total
Number of hi-fi systems sold in the morning
= 4 u - 1 u
= 3 u
3 u = 30
1 u = 30 ÷ 3 = 10
Number of hi-fi systems left
= 2 u
= 2 x 10
= 20
Answer(s): 20