Barbara and Linda collected marbles. Linda gave 60% of her marbles to Barbara. As a result, Barbara's marbles increased by 40%. If Barbara had 231 marbles left, find the total number of marbles the two girls had at first.
| |
Comparing the change
in Linda's marbles |
Linda |
Barbara |
| Before |
5x2 =
10 u |
|
5x3 =
15 u |
| Change |
- 3x2 =
- 6 u |
- 2x3 =
- 6 u |
+ 2x3 =
+ 6 u |
| After |
2x2 =
4 u |
|
7x3 =
21 u |
60% =
60100 =
35 40% =
40100 =
25 The number of marbles that Barbara gave to Linda is repeated. Make the number of marbles that Barbara gave to Linda the same. LCM of 2 and 3 is 6.
Number of marbles that Barbara had in the end = 21 u
21 u = 231
1 u = 231 ÷ 21 = 11
Number of marbles that Linda and Barbara had at first
= 10 u + 15 u
= 25 u
= 25 x 11
= 275
Answer(s): 275
