Ryan, Justin and Julian had a total of 40 beads. The ratio of Justin's beads to Julian's beads was 4 : 3 at first. Ryan and Justin each gave away
12 of their beads. Given that the three boys had 26 beads left, how many beads did Ryan have in the end?
|
Ryan |
Justin |
Julian |
Total |
Comparing Justin and Julian at first |
|
4 u |
3 u |
|
Before |
2 p |
2x2 = 4 u |
3 u |
40 |
Change |
- 1 p |
-1x2 = - 2 u |
|
- 14 |
After |
1 p |
1x2 = 2 u |
3 u |
26 |
Total number of beads that Ryan and Justin gave away
= 40 - 26
= 14
The number of beads that Justin had at first is repeated. Make the number of beads that Justin had at first the same. LCM of 4 and 2 is 4.
1 p + 2 u = 40 - 26
1 p + 2 u = 14
1 p = 14 - 2 u --- (1)
1 p + 2 u + 3 u = 26
1 p + 5 u = 26
1 p = 26 - 5 u --- (2)
(1) = (2)
14 - 2 u = 26 - 5 u
5 u - 2 u = 26 - 14
5 u - 2 u = 12
3 u = 12
1 u = 12 ÷ 3 = 4
Substitute 1 u = 4 into (1).
1 p = 14 - 2 u
1 p = 14 - 2 x 4
1 p = 14 - 8
1 p = 6
Number of beads that Ryan had in the end
= 1 p
= 6
Answer(s): 6