Yoko had some marble collection.
34 of them were brown and the rest were blue. She gave away 121 of the blue marbles and 20% of the brown marbles. She then had
23 of her marble collection left. How many marbles did Yoko give away?
| |
Brown |
Blue |
Total |
Total |
Before
|
3x3 =
9 u |
1x3 =
3 u |
4x3 =
12 u |
3x4 =
12 u |
Change
|
- 0.6x3 =
- 1.8 u |
- 121 |
|
- 1x4 =
- 4 u |
After
|
2.4x3 =
7.2 u |
3 u - 121 |
|
2x4 =
8 u |
The total number of marbles that Yoko had at first is repeated. Make the total number of marbles at first the same. LCM 4 and 3 is 12.
Number of brown marbles that Yoko gave away
= 20% x 3 u
=
20100 x 3 u
= 0.6 u
1.8 u - 121 = 4 u
4 u - 1.8 u = 121
2.2 u = 121
1 u = 121 ÷ 2.2 = 55
Number of marbles that Yoko gave away
= 4 u
= 4 x 55
= 220
Answer(s): 220
