The ratio of Charlotte's stamps to Harris's stamps at first was 3 : 7. After Charlotte gave Harris 86 stamps, the ratio of Charlotte's stamps to Harris's stamps is 1 : 3. What was the number of stamps they had altogether?
| |
Charlotte |
Harris |
Total |
| Before |
3x4 =
12 u |
7x4 =
28 u
|
10x4 =
40 u |
| Change |
- 86 |
+ 86 |
|
| After |
1x10 =
10 u |
3x10 =
30 u |
4x10 =
40 u |
Number of stamps that Charlotte gave Harris
= 12 u - 10 u
= 2 u
2 u = 86
1 u = 86 ÷ 2 = 43
Total number of stamps that they had
= 40 u
= 40 x 43
= 1720
Answer(s): 1720
