Fanny and Xandra collected stamps. Fanny gave 10% of her stamps to Xandra. As a result, Xandra's stamps increased by 70%. If Fanny had 441 stamps left, find the total number of stamps the two girls had at first.
| |
Fanny |
Xandra |
Comparing the change
in Xandra's stamps |
| Before |
10x7 =
70 u |
|
10x1 =
10 u |
| Change |
- 1x7 =
- 7 u |
+ 1x7 =
+ 7 u |
+ 7x1 =
+ 7 u |
| After |
9x7 =
63 u |
|
17x1 =
17 u |
10% =
10100 =
110 70% =
70100 =
710 The number of stamps that Fanny gave to Xandra is repeated. Make the number of stamps that Fanny gave to Xandra the same. LCM of 1 and 7 is 7.
Number of stamps that Fanny had in the end = 63 u
63 u = 441
1 u = 441 ÷ 63 = 7
Number of stamps that Fanny and Xandra had at first
= 70 u + 10 u
= 80 u
= 80 x 7
= 560
Answer(s): 560
