Riordan had $1.80 less than Andy. After Riordan gave $3.90 to Andy, Andy would have thrice as much money as Riordan. How much money had Andy at first?
| |
Andy |
Riordan |
| Before |
3 u - $3.90 |
1 u + $3.90 |
| Change |
+ $3.90 |
- $3.90 |
| After |
3 u |
1 u |
Riordan had $1.80 less than Andy. If another $1.80 was given to Riordan, Andy and Riordan would have the same amount at first.
3 u - 3.90 = 1 u + 3.90 + 1.80
3 u - 1 u = 3.90 + 1.80 + 3.90
2 u = 9.60
1 u = 9.60 ÷ 2 = 4.80
Amount that Andy had at first
= 3 u - 3.90
= 3 x 4.80 + 3.90
= 14.40 + 3.90
= $18.30
Answer(s): $18.30
