Betty and Kylie went shopping. After Betty spent $77
a, Kylie had 3 times as much as Betty. If Betty had $28
a more than Kylie at first,
- Express the amount of money that Betty had at first in terms of a.
- If a = 10, find the amount of money that the two lady had left after shopping.
|
Betty |
Kylie |
Before |
1 u + $77a |
3 u |
Change |
- $77a |
|
After |
1 u |
3 u |
(a)
1 u + 77
a = 3 u + 28
a3 u - 1 u = 77
a - 28
a2 u = 77
a - 28
a = 49
a1 u = 49
a ÷ 2 = 24.5
a Betty's amount at first
= 1 u + 77
a = 24.5
a + 77
a = $101.5
a (b)
1 u + 3 u = 4 u
4 u = 4 x 24.5
a = 98
a Amount the two lady had left
= 98 x 10
= $980
Answer(s): (a) $101.5
a; (b) $980