Min and Jean collected coins. Min gave 20% of her coins to Jean. As a result, Jean's coins increased by 70%. If Min had 336 coins left, find the total number of coins the two girls had at first.
| |
Min |
Jean |
Comparing the change
in Jean's coins |
| Before |
5x7 =
35 u |
|
10x1 =
10 u |
| Change |
- 1x7 =
- 7 u |
+ 1x7 =
+ 7 u |
+ 7x1 =
+ 7 u |
| After |
4x7 =
28 u |
|
17x1 =
17 u |
20% =
20100 =
15 70% =
70100 =
710 The number of coins that Min gave to Jean is repeated. Make the number of coins that Min gave to Jean the same. LCM of 1 and 7 is 7.
Number of coins that Min had in the end = 28 u
28 u = 336
1 u = 336 ÷ 28 = 12
Number of coins that Min and Jean had at first
= 35 u + 10 u
= 45 u
= 45 x 12
= 540
Answer(s): 540
