Gillian and Lynn have some erasers. If Gillian gives 16 erasers to Lynn, Lynn will have 5 times the number of erasers as Gillian. If Lynn gives 79 erasers to Gillian, Gillian will have
35 as many erasers as Lynn. How many erasers does Gillian have at first?
|
Case 1 |
Case 2 |
|
Gillian |
Lynn |
Gillian |
Lynn |
Before |
4 u + 16 |
20 u - 16 |
9 u - 79 |
15 u + 79 |
Change |
- 16 |
+ 16 |
+ 79 |
- 79 |
After |
1x4 = 4 u |
5x4 = 20 u |
3x3 = 9 u |
5x3 = 15 u |
The total number of erasers in both cases remains unchanged. Make the total number of erasers in both cases the same. LCM of 6 and 8 is 24.
Number of erasers that Gillian had at first is the same in both cases.
9 u - 79 = 4 u + 16
9 u - 4 u = 16 + 79
5 u = 95
1 u = 19
Number of erasers that Gillian had at first
= 4 u + 16
= 4 x 19 + 16
= 76 + 16
= 92
Answer(s): 92