There were some grapefruits at a shop. In the morning,
14 of grapefruits were sold. In the afternoon, another 28 grapefruits were sold. The total number of grapefruits sold was 4 less than
712 of the number of grapefruits the shop had at first.
- How many grapefruits were there at first?
- What fraction of the grapefruits in the shop remained unsold in the afternoon?
|
Comparison 1 |
Comparison 2 |
Before |
4x3 = 12 u |
12x1 = 12 u |
Change 1 |
- 1x3 = - 3 u |
|
After 1 |
3x3 = 9 u |
Change 2 |
- 28 |
After 2 |
9 u - 28 |
7x1 - 4 = 7 u - 4 |
(a)
The number of grapefruits at first is repeated in both comparisons. Make the number of grapefruits at first. LCM of 4 and 12 is 12.
The number of grapefruits in the end is the same in both comparisons.
9 u - 28 = 7 u - 4
9 u - 7 u = 28 - 4
4 u = 32
1 u = 32 ÷ 4 = 8
Number of grapefruits at first
= 12 u
= 12 x 8
= 96
(b)
Number of grapefruits that remained unsold
= 5 u + 4
= 5 x 8 + 4
= 44
Fraction of grapefruits that remained unsold
=
4496=
1124Answer(s): (a) 96; (b)
1124