Liam saved $9 each day and Zara saved $
f more than Liam each day. After 6 weeks, they were still short of $28 to buy a hi-fi system.
- How much did the hi-fi system cost? Express your answer in terms of f.
- If f = $14, how much did the hi-fi system cost?
(a)
Amount Liam saved per day = $9
Amount Zara saved per day = $(9 +
f)
Total amount both saved per day
= 9 + 9 +
f = $(18 +
f)
Number of days in 6 weeks
= 6 x 7
= 42
Total both saved in 6 weeks
= 42(18 +
f)
= 42 x 18 + 42 x
f = $(756 + 42
f)
Cost of the hi-fi system
= 756 + 42
f + 28
= 756 + 28 + 42
f= $(784 + 42
f)
(b)
If
f = $14,
Cost of the hi-fi system
= 784 + 42 x 14
= 784 + 588
= $1372
Answer(s): (a) $(784 + 42
f) or $(42
f + 784); (b) $1372
