Albert saved $10 each day and Mary saved $
j more than Albert each day. After 2 weeks, they were still short of $30 to buy a stereo system.
- How much did the stereo system cost? Express your answer in terms of j.
- If j = $4, how much did the stereo system cost?
(a)
Amount Albert saved per day = $10
Amount Mary saved per day = $(10 +
j)
Total amount both saved per day
= 10 + 10 +
j = $(20 +
j)
Number of days in 2 weeks
= 2 x 7
= 14
Total both saved in 2 weeks
= 14(20 +
j)
= 14 x 20 + 14 x
j = $(280 + 14
j)
Cost of the stereo system
= 280 + 14
j + 30
= 280 + 30 + 14
j= $(310 + 14
j)
(b)
If
j = $4,
Cost of the stereo system
= 310 + 14 x 4
= 310 + 56
= $366
Answer(s): (a) $(310 + 14
j) or $(14
j + 310); (b) $366
