Xandra had some button collection.
13 of them were green and the rest were brown. She gave away 186 of the brown buttons and 30% of the green buttons. She then had
18 of her button collection left. How many buttons did Xandra give away?
|
Green |
Brown |
Total |
Total |
Before
|
1x8 = 8 u |
2x8 = 16 u |
3x8 = 24 u |
8x3 = 24 u |
Change
|
- 0.3x8 = - 2.4 u |
- 186 |
|
- 7x3 = - 21 u |
After
|
0.7x8 = 5.6 u |
16 u - 186 |
|
1x3 = 3 u |
The total number of buttons that Xandra had at first is repeated. Make the total number of buttons at first the same. LCM 3 and 8 is 24.
Number of green buttons that Xandra gave away
= 30% x 1 u
=
30100 x 1 u
= 0.3 u
2.4 u - 186 = 21 u
21 u - 2.4 u = 186
18.6 u = 186
1 u = 186 ÷ 18.6 = 10
Number of buttons that Xandra gave away
= 21 u
= 21 x 10
= 210
Answer(s): 210