Cindy has 2 times as many puffs as Fiona. The total number of Cindy's and Fiona's puffs is 7 times of Kathy's. Cindy and Fiona have 108 puffs more than Kathy's. How many more puffs does Cindy have than Fiona?
| Cindy |
Fiona |
Kathy |
| 2x7 |
1x7 |
|
| 7x3 |
1x3 |
| 14 u |
7 u |
3 u |
The total number of puffs that Cindy and Fiona have is repeated. Make the total number of puffs that Cindy and Fiona have the same. LCM of 3 and 7 is 21.
Total number of puffs that Cindy and Fiona have
= 14 u + 7 u
= 21 u
Number of more puffs that Cindy and Fiona have than Kathy
= 21 u - 3 u
= 18 u
18 u = 108
1 u = 108 ÷ 18 = 6
Number of more puffs that Cindy has than Fiona
= 14 u - 7 u
= 7 u
= 7 x 6
= 42
Answer(s): 42
