Mary has 3 times as many erasers as Yoko. Yoko has
35 as many erasers as Sarah. If the three of them have a total of 34 erasers, how many erasers does Mary have?
Mary |
Yoko |
Sarah |
3x3 |
1x3 |
|
|
3x1 |
5x1 |
9 u |
3 u |
5 u |
The number of erasers that Yoko has is repeated. Make the number of erasers that Yoko has the same. LCM of 1 and 3 is 3.
Total number of erasers that the three of them have
= 9 u + 3 u + 5 u
= 17 u
17 u = 34
1 u = 34 ÷ 17 = 2
Number of erasers that Mary has
= 9 u
= 9 x 2
= 18
Answer(s): 18