Fred bought some coupons for a funfair. He used
25 of the coupons on food and
37 of the remainder on games. He bought another 90 coupons and had 21 more coupons than he had at first. How many coupons did he have at first?
| Food |
Remainder |
Bought |
Total |
2x7 =
14 u |
3x7 =
21 u |
|
5x7 =
35 u |
| |
Games |
Left |
|
|
| |
3x3 |
4x3 |
|
|
| 14 u |
9 u |
12 u |
90 |
35 u |
The remaining number of coupons before Fred bought another 90 coupons is repeated. Make the remaining number of coupons the same. LCM of 3 and 7 is 21.
Total number of coupons at first = 35 u
Total number of coupons in the end = 12 u + 90
Number of coupons left was 21 more than the number of coupons at first.
35 u + 21 = 12 u + 90
35 u - 12 u = 90 - 21
23 u = 69
1 u = 69 ÷ 23 = 3
Total number of coupons at first
= 35 u
= 35 x 3
= 105
Answer(s): 105
