Tammy and Mary collected coins. Tammy gave 25% of her coins to Mary and as a result, Mary's coins increased by 30%. If Tammy had 45 coins left, find the number of coins Mary should give to Tammy in the end so that both had an equal number of coins.
| |
Tammy
|
Mary |
Comparing the change
in Mary's coins
|
|
Before
|
4x3 =
12 u |
|
10x1 =
10u |
|
Change
|
- 1x3 =
- 3 u
|
+ 1x3 =
+ 3 u
|
+ 3x1 =
+ 3 u
|
|
After
|
3x3 =
9 u
|
|
13x1 =
13 u |
25% =
25100 =
1430% =
30100 =
310The increase in the number of coins that Mary had is repeated. Make the increase in the number of coins that Mary had the same. LCM of 1 and 3 = 3
9 u = 45
1 u = 45 ÷ 9 = 5
Number of coins that Mary had more than Tammy in the end
= 13 u - 9 u
= 4 u
Number of coins that Mary should give to Tammy so that both had an equal number of coins in the end
= 4 u ÷ 2
= 2 u
= 2 x 5
= 10
Answer(s): 10
