Nora had 90% as many chocolate bars as Linda. Nora gave away 20% of her chocolate bars and Linda bought another 40 chocolate bars. As a result, Nora now has 70% as many chocolate bars as Linda. Find the number of chocolate bars that Linda had at first.
| |
Nora |
Linda |
| Before |
9x7 |
10x7 |
| Change |
- 1.8x7 |
+ 40 |
| After |
7.2x7 |
10x7 + 40 |
Comparing Nora and
Linda in the end |
7x7.2 |
10x7.2 |
| |
Nora |
Linda |
| Before |
63 u |
70 u |
| Change |
- 12.6 u |
+ 40 |
After
|
50.4 u
|
70 u + 40 =
72 u |
90% =
90100 =
91020% x 9
=
20100 x 9
= 1.8
70% =
70100 =
710The number of chocolate bars that Nora had in the end is repeated.
Make the number of chocolate bars that Nora had in the end the same.
The number of chocolate bars that Linda had in the end is repeated.
70 u + 40 = 72 u
72 u - 70 u = 40
2 u = 40
1 u = 40 ÷ 2 = 20
Number of chocolate bars that Linda had at first
= 70 u
= 70 x 20
= 1400
Answer: 1400
