Diana and Irene had an equal number of cards at first. Diana used
12 of her cards and Irene used
18 of her cards. They used 10 cards altogether. How many cards did Irene have in the end?
| |
Diana |
Irene |
| Before |
2x4 =
8 u |
8x1 =
8 u |
| Change |
- 1x4 =
- 4 u |
- 1x1 =
- 1 u |
| After |
1x4 =
4 u |
7x1 =
7 u |
The number of cards that Diana and Irene each had at first is the same. Make the number of cards that Diana and Irene each had at first the same. LCM of 2 and 8 is 8.
Number of cards that Diana and Irene used
= 4 u + 1 u
= 5 u
5 u = 10
1 u = 10 ÷ 5 = 2
Number of cards that Irene had in the end
= 7 u
= 7 x 2
= 14
Answer(s): 14
