Lynn had a total of 444 purple and black beads. She used
37 of her purple beads and bought another 63 black beads. The number of black beads she had then become
15 the number of purple beads. How many less black beads than purple beads did she have at first?
| |
Purple beads |
Black beads |
| Before |
7x5 |
|
| Change |
- 3x5 |
+ 63 |
| After |
4x5 |
|
| Comparing beads in the end |
5x4 |
1x4 |
| |
Purple beads |
Black beads |
| Before |
35 u |
4 u - 63 |
| Change |
- 15 u |
+ 63 |
| After |
20 u |
4 u |
The number of purple beads in the end is repeated.
LCM of 4 and 5 is 20.
Total number of purple beads and black beads
= 35 u + 4 u - 63
= 39 u - 63
39 u - 63 = 444
39 u = 444 + 63
39 u = 507
1 u = 507 ÷ 39 = 13
Number of less black beads than purple beads at first
= 35 u - (4 u - 63)
= 31 u + 63
= 31 x 13 + 63
= 466
Answer(s): 466
