Tiffany and Shannon went shopping. After Tiffany spent $66
i, Shannon had 3 times as much as Tiffany. If Tiffany had $30
i more than Shannon at first,
- Express the amount of money that Tiffany had at first in terms of i.
- If i = 21, find the amount of money that the two lady had left after shopping.
|
Tiffany |
Shannon |
Before |
1 u + $66i |
3 u |
Change |
- $66i |
|
After |
1 u |
3 u |
(a)
1 u + 66
i = 3 u + 30
i3 u - 1 u = 66
i - 30
i2 u = 66
i - 30
i = 36
i1 u = 36
i ÷ 2 = 18
i Tiffany's amount at first
= 1 u + 66
i = 18
i + 66
i = $84
i (b)
1 u + 3 u = 4 u
4 u = 4 x 18
i = 72
i Amount the two lady had left
= 72 x 21
= $1512
Answer(s): (a) $84
i; (b) $1512