Esther has 4 times as many erasers as Dana. Dana has
57 as many erasers as Cathy. If the three of them have a total of 288 erasers, how many erasers does Cathy have?
Esther |
Dana |
Cathy |
4x5 |
1x5 |
|
|
5x1 |
7x1 |
20 u |
5 u |
7 u |
The number of erasers that Dana has is repeated. Make the number of erasers that Dana has the same. LCM of 1 and 5 is 5.
Total number of erasers that the three of them have
= 20 u + 5 u + 7 u
= 32 u
32 u = 288
1 u = 288 ÷ 32 = 9
Number of erasers that Cathy has
= 7 u
= 7 x 9
= 63
Answer(s): 63