Min and Jane had an equal number of marbles at first. Min used
12 of her marbles and Jane used
17 of her marbles. They used 81 marbles altogether. How many marbles did Jane have in the end?
|
Min |
Jane |
Before |
2x7 = 14 u |
7x2 = 14 u |
Change |
- 1x7 = - 7 u |
- 1x2 = - 2 u |
After |
1x7 = 7 u |
6x2 = 12 u |
The number of marbles that Min and Jane each had at first is the same. Make the number of marbles that Min and Jane each had at first the same. LCM of 2 and 7 is 14.
Number of marbles that Min and Jane used
= 7 u + 2 u
= 9 u
9 u = 81
1 u = 81 ÷ 9 = 9
Number of marbles that Jane had in the end
= 12 u
= 12 x 9
= 108
Answer(s): 108