Eight hours ago, a grocer started his day with some oranges and mangosteens in the ratio of 8 : 7. There were 140 mangosteens. Some of the oranges were bought by Fiona. As a result, the number of oranges became
25 of the mangosteens.
- How many oranges did the grocer have left?
- How many oranges did the grocer have to buy in order to have an equal number of oranges and mangosteens?
|
Oranges |
Mangosteens |
Before |
8x5 = 40 u |
7x5 = 35 u |
Change |
- ? |
|
After |
2x7 = 14 u |
5x7 = 35 u |
(a)
The number of mangosteens remains unchanged. Make the number of mangosteens the same. LCM of 7 and 5 is 35.
35 u = 140
1 u = 140 ÷ 35 = 4
Number of oranges that the grocer had left
= 14 u
= 14 x 4
= 56
(b)
Number of oranges that the grocer had to buy to have an equal number of oranges and mangosteens
= 35 u - 14 u
= 21 u
= 21 x 4
= 84
Answer(s): (a) 56; (b) 84