Jade had 90% as many sweets as Yoko. Jade gave away 20% of her sweets and Yoko bought another 20 sweets. As a result, Jade now has 70% as many sweets as Yoko. Find the number of sweets that Yoko had at first.
| |
Jade |
Yoko |
| Before |
9x7 |
10x7 |
| Change |
- 1.8x7 |
+ 20 |
| After |
7.2x7 |
10x7 + 20 |
Comparing Jade and
Yoko in the end |
7x7.2 |
10x7.2 |
| |
Jade |
Yoko |
| Before |
63 u |
70 u |
| Change |
- 12.6 u |
+ 20 |
After
|
50.4 u
|
70 u + 20 =
72 u |
90% =
90100 =
91020% x 9
=
20100 x 9
= 1.8
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 Yoko had in the end is repeated.
70 u + 20 = 72 u
72 u - 70 u = 20
2 u = 20
1 u = 20 ÷ 2 = 10
Number of sweets that Yoko had at first
= 70 u
= 70 x 10
= 700
Answer: 700
