Kimberly and Mary have some coins. If Kimberly gives 17 coins to Mary, Mary will have 4 times the number of coins as Kimberly. If Mary gives 18 coins to Kimberly, Kimberly will have
35 as many coins as Mary. How many coins does Kimberly have at first?
|
Case 1 |
Case 2 |
|
Kimberly |
Mary |
Kimberly |
Mary |
Before |
8 u + 17 |
32 u - 17 |
15 u - 18 |
25 u + 18 |
Change |
- 17 |
+ 17 |
+ 18 |
- 18 |
After |
1x8 = 8 u |
4x8 = 32 u |
3x5 = 15 u |
5x5 = 25 u |
The total number of coins in both cases remains unchanged. Make the total number of coins in both cases the same. LCM of 5 and 8 is 40.
Number of coins that Kimberly had at first is the same in both cases.
15 u - 18 = 8 u + 17
15 u - 8 u = 17 + 18
7 u = 35
1 u = 5
Number of coins that Kimberly had at first
= 8 u + 17
= 8 x 5 + 17
= 40 + 17
= 57
Answer(s): 57