Xuan had 90% as many chocolate bars as Barbara. Xuan gave away 25% of her chocolate bars and Barbara bought another 30 chocolate bars. As a result, Xuan now has 60% as many chocolate bars as Barbara. Find the number of chocolate bars that Xuan had in the end.
| |
Xuan |
Barbara |
| Before |
9x3 |
10x3 |
| Change |
- 2.25x3 |
+ 30 |
| After |
6.75x3 |
10x3 + 30 |
Comparing Xuan and
Barbara in the end |
3x6.75 |
5x6.75 |
| |
Xuan |
Barbara |
| Before |
27 u |
30 u |
| Change |
- 6.75 u |
+ 30 |
After
|
20.25 u
|
30 u + 30 =
33.75 u |
90% =
90100 =
91025% x 9
=
25100 x 9
= 2.25
60% =
60100 =
35The number of chocolate bars that Xuan had in the end is repeated.
Make the number of chocolate bars that Xuan had in the end the same.
The number of chocolate bars that Barbara had in the end is repeated.
30 u + 30 = 33.75 u
33.75 u - 30 u = 30
3.75 u = 30
1 u = 30 ÷ 3.75 = 8
Number of chocolate bars that Xuan had in the end
= 20.25 u
= 20.25 x 8
= 162
Answer: 162
