Penelope and Joelle collected marbles. Penelope gave 40% of her marbles to Joelle. As a result, Joelle's marbles increased by 70%. If Penelope had 63 marbles left, find the total number of marbles the two girls had at first.
| |
Penelope |
Joelle |
Comparing the change
in Joelle's marbles |
| Before |
5x7 =
35 u |
|
10x2 =
20 u |
| Change |
- 2x7 =
- 14 u |
+ 2x7 =
+ 14 u |
+ 7x2 =
+ 14 u |
| After |
3x7 =
21 u |
|
17x2 =
34 u |
40% =
40100 =
25 70% =
70100 =
710 The number of marbles that Penelope gave to Joelle is repeated. Make the number of marbles that Penelope gave to Joelle the same. LCM of 2 and 7 is 14.
Number of marbles that Penelope had in the end = 21 u
21 u = 63
1 u = 63 ÷ 21 = 3
Number of marbles that Penelope and Joelle had at first
= 35 u + 20 u
= 55 u
= 55 x 3
= 165
Answer(s): 165
