PSLE A shop had a number of stereo systems for sale. After selling 20 of them in the morning and
29 of the remainder in the afternoon, it was left with
12 of the stereo systems. How many stereo systems were sold altogether?
Morning |
Remainder |
|
Afternoon |
Left |
20 |
2x1 |
7x1 |
1x7 |
1x7 |
5 u |
2 u |
7 u |
Fraction of the remainder left
= 1 -
29 =
79 7x19x1 Remainder =
1x72x7 Total
79 Remainder =
714 Total
Number of stereo systems sold in the morning
= 7 u - 2 u
= 5 u
5 u = 20
1 u = 20 ÷ 5 = 4
Total number of stereo systems sold
= 7 u
= 7 x 4
= 28
Answer(s): 28