Anna bought some cards. She gave
15 of the cards to her sister and sold
35 of the remaining cards. After that, she bought another 34 cards and had the same number of cards that she bought at first. How many cards did Anna buy at first?
| Her sister |
Remaining cards |
Bought cards |
Total |
1x5 =
5 u |
4x5 =
20 u |
|
5x5 =
25 u |
| |
Sold |
Left |
|
|
| |
3x4 |
2x4 |
|
|
| 5 u |
12 u |
8 u |
34 |
|
The remaining number of cards before Anna bought another 34 cards is repeated. Make the remaining number of cards the same. LCM of 4 and 5 is 20.
Total number of cards at first = 25 u
Number of cards that Anna had left and bought after that = 8 u + 34
25 u = 8 u + 34
25 u - 8 u = 34
17 u = 34
1 u = 34 ÷ 17 = 2
Total number of cards at first
= 25 u
= 25 x 2
= 50
Answer(s): 50
