There were some starfruits at a stall. In the morning,
13 of starfruits were sold. In the afternoon, another 36 starfruits were sold. The total number of starfruits sold was 9 less than
712 of the number of starfruits the stall had at first.
- How many starfruits were there at first?
- What fraction of the starfruits in the stall remained unsold in the afternoon?
|
Comparison 1 |
Comparison 2 |
Before |
3x4 = 12 u |
12x1 = 12 u |
Change 1 |
- 1x4 = - 4 u |
|
After 1 |
2x4 = 8 u |
Change 2 |
- 36 |
After 2 |
8 u - 36 |
7x1 - 9 = 7 u - 9 |
(a)
The number of starfruits at first is repeated in both comparisons. Make the number of starfruits at first. LCM of 3 and 12 is 12.
The number of starfruits in the end is the same in both comparisons.
8 u - 36 = 7 u - 9
8 u - 7 u = 36 - 9
3 u = 45
1 u = 45 ÷ 3 = 15
Number of starfruits at first
= 12 u
= 12 x 15
= 180
(b)
Number of starfruits that remained unsold
= 5 u + 9
= 5 x 15 + 9
= 84
Fraction of starfruits that remained unsold
=
84180=
715Answer(s): (a) 180; (b)
715