Bobby and Albert had some erasers in the ratio of 8 : 7. Albert and Tim had some erasers in the ratio of 4 : 1. Bobby sold 126 erasers to Tim and ended up with half the number of erasers Albert had. How many erasers did Tim have in the end?
| Bobby |
Albert |
Tim |
| 8x4 |
7x4 |
|
| |
4x7 |
1x7 |
| 32 u |
28 u |
7 u |
The number of erasers that Albert had at first is repeated. Make the number of erasers that Albert had at first the same. LCM of 7 and 4 is 28.
| |
Bobby |
Albert |
Tim |
| Before |
32 u |
28 u |
7 u |
| Change |
- 126 |
|
+ 126 |
| After |
14 u |
28 u |
7 u + 126 |
Number of erasers that Bobby had in the end
= 28 u ÷ 2
= 14 u
Number of erasers that Bobby sold to Tim
= 32 u - 14 u
= 18 u
18 u = 126
1 u = 126 ÷ 18 = 7
Number of erasers that Tim had in the end
= 7 u + 126
= 7 x 7 + 126
= 49 + 126
= 175
Answer(s): 175
