Lui saved $10 each day and Tammy saved $
z more than Lui each day. After 3 weeks, they were still short of $32 to buy a projector.
- How much did the projector cost? Express your answer in terms of z.
- If z = $13, how much did the projector cost?
(a)
Amount Lui saved per day = $10
Amount Tammy saved per day = $(10 +
z)
Total amount both saved per day
= 10 + 10 +
z = $(20 +
z)
Number of days in 3 weeks
= 3 x 7
= 21
Total both saved in 3 weeks
= 21(20 +
z)
= 21 x 20 + 21 x
z = $(420 + 21
z)
Cost of the projector
= 420 + 21
z + 32
= 420 + 32 + 21
z= $(452 + 21
z)
(b)
If
z = $13,
Cost of the projector
= 452 + 21 x 13
= 452 + 273
= $725
Answer(s): (a) $(452 + 21
z) or $(21
z + 452); (b) $725
