Jade had 90% as many sweets as Olivia. Jade gave away 10% of her sweets and Olivia bought another 220 sweets. As a result, Jade now has 70% as many sweets as Olivia. Find the number of sweets that Olivia had at first.
| |
Jade |
Olivia |
| Before |
9x7 |
10x7 |
| Change |
- 0.9x7 |
+ 220 |
| After |
8.1x7 |
10x7 + 220 |
Comparing Jade and
Olivia in the end |
7x8.1 |
10x8.1 |
| |
Jade |
Olivia |
| Before |
63 u |
70 u |
| Change |
- 6.3 u |
+ 220 |
After
|
56.7 u
|
70 u + 220 =
81 u |
90% =
90100 =
91010% x 9
=
10100 x 9
= 0.9
70% =
70100 =
710The number of sweets that Jade had in the end is repeated.
Make the number of sweets that Jade had in the end the same.
The number of sweets that Olivia had in the end is repeated.
70 u + 220 = 81 u
81 u - 70 u = 220
11 u = 220
1 u = 220 ÷ 11 = 20
Number of sweets that Olivia had at first
= 70 u
= 70 x 20
= 1400
Answer: 1400
