There were some peaches at a supermarket. In the morning,
16 of peaches were sold. In the afternoon, another 21 peaches were sold. The total number of peaches sold was 2 less than
57 of the number of peaches the supermarket had at first.
- How many peaches were there at first?
- What fraction of the peaches in the supermarket remained unsold in the afternoon?
|
Comparison 1 |
Comparison 2 |
Before |
6x7 = 42 u |
7x6 = 42 u |
Change 1 |
- 1x7 = - 7 u |
|
After 1 |
5x7 = 35 u |
Change 2 |
- 21 |
After 2 |
35 u - 21 |
5x6 - 2 = 30 u - 2 |
(a)
The number of peaches at first is repeated in both comparisons. Make the number of peaches at first. LCM of 6 and 7 is 42.
The number of peaches in the end is the same in both comparisons.
35 u - 21 = 30 u - 2
35 u - 30 u = 21 - 2
23 u = 23
1 u = 23 ÷ 23 = 1
Number of peaches at first
= 42 u
= 42 x 1
= 42
(b)
Number of peaches that remained unsold
= 12 u + 2
= 12 x 1 + 2
= 14
Fraction of peaches that remained unsold
=
1442=
13Answer(s): (a) 42; (b)
13