Penelope and Esther collected marbles. Esther gave 80% of her marbles to Penelope. As a result, Penelope's marbles increased by 40%. If Penelope had 168 marbles left, find the total number of marbles the two girls had at first.
| |
Comparing the change
in Esther's marbles |
Esther |
Penelope |
| Before |
5x1 =
5 u |
|
5x2 =
10 u |
| Change |
- 4x1 =
- 4 u |
- 2x2 =
- 4 u |
+ 2x2 =
+ 4 u |
| After |
1x1 =
1 u |
|
7x2 =
14 u |
80% =
80100 =
45 40% =
40100 =
25 The number of marbles that Penelope gave to Esther is repeated. Make the number of marbles that Penelope gave to Esther the same. LCM of 2 and 4 is 4.
Number of marbles that Penelope had in the end = 14 u
14 u = 168
1 u = 168 ÷ 14 = 12
Number of marbles that Esther and Penelope had at first
= 5 u + 10 u
= 15 u
= 15 x 12
= 180
Answer(s): 180
