Rael, Caden and Japheth had 105 coins. After Rael used 37 coins and Caden used
16 of her coins, Rael had twice as many coins left as Caden. Japheth bought another 40 coins, he had four times the number of coins Caden had left. How many coins did Japheth have at first?
| |
Rael |
Caden |
Japheth |
Total |
| Before |
10 u + 37 |
6 u |
20 u - 40 |
105 |
| Change |
- 37 |
- 1 u |
+ 40 |
|
| After |
10 u |
5 u |
20 u |
|
Comparing Rael
and Caden in the end |
2 |
1 |
|
|
Comparing Japheth
and Caden in the end |
|
1 |
4 |
|
Number of coins that Rael had in the end
= 2 x 5 u
= 10 u
Number of coins that Japheth had in the end
= 4 x 5 u
= 20 u
Total number of coins at first
= 10 u + 37 + 6 u + 20 u - 40
= 36 u - 3
36 u - 3 = 105
36 u = 105 + 3
36 u = 108
1 u = 108 ÷ 36 = 3
Number of coins that Japheth had at first
= 20 u - 40
= 20 x 3 - 40
= 60 - 40
= 20
Answer(s): 20
