PSLE A shop had a number of hard drives for sale. After selling 21 of them in the morning and
13 of the remainder in the afternoon, it was left with
15 of the hard drives. How many hard drives were sold altogether?
Morning |
Remainder |
|
Afternoon |
Left |
21 |
1x1 |
2x1 |
4x2 |
1x2 |
7 u |
1 u |
2 u |
Fraction of the remainder left
= 1 -
13 =
23 2x13x1 Remainder =
1x25x2 Total
23 Remainder =
210 Total
Number of hard drives sold in the morning
= 8 u - 1 u
= 7 u
7 u = 21
1 u = 21 ÷ 7 = 3
Total number of hard drives sold
= 8 u
= 8 x 3
= 24
Answer(s): 24