A convenience store sold jam, club and ham sandwiches. The ratio of the number of jam sandwiches made to the total number of sandwiches made was 5 : 7. The ratio of the number of club sandwiches made to the total number of sandwiches made was 1 : 9. After the store sold some jam sandwiches and made another 24 club sandwiches, there was an equal number of jam, club and ham sandwiches left. Find the number of jam sandwiches sold.
|
Jam |
Club |
Ham |
Total |
Comparing jam to total |
5x9 |
|
|
7x9 |
Comparing club to total |
|
1x7 |
|
9x7 |
|
45 u |
7 u |
11 u |
63 u |
|
Jam |
Club |
Ham |
Total |
Before |
45 u |
7 u |
11 u |
63 u |
Change |
- 34 u |
+ 24 |
No change |
|
After |
1x11 = 11 u |
1x11 = 11 u |
1x11 = 11 u |
|
The total number of sandwiches is the same at first. Make the total number of sandwiches the same. LCM of 9 and 7 is 63.
Number of ham sandwiches remains the same at first and in the end. Make the number of ham sandwiches the same. LCM of 1 and 11 is 11.
Number of ham sandwiches
= 63 u - 45 u - 7 u
= 11 u
Number of jam, club and ham sandwiches is the same in the end.
Number of club sandwiches = 7 u + 24
7 u + 24 = 11 u
11 u - 7 u = 24
4 u = 24
1 u = 24 ÷ 4 = 6
Number of jam sandwiches sold
= 45 u - 11 u
= 34 u
= 34 x 6
= 204
Answer(s): 204