Tim saved $10 each day and Anna saved $
g more than Tim each day. After 3 weeks, they were still short of $32 to buy a mobile phone.
- How much did the mobile phone cost? Express your answer in terms of g.
- If g = $4, how much did the mobile phone cost?
(a)
Amount Tim saved per day = $10
Amount Anna saved per day = $(10 +
g)
Total amount both saved per day
= 10 + 10 +
g = $(20 +
g)
Number of days in 3 weeks
= 3 x 7
= 21
Total both saved in 3 weeks
= 21(20 +
g)
= 21 x 20 + 21 x
g = $(420 + 21
g)
Cost of the mobile phone
= 420 + 21
g + 32
= 420 + 32 + 21
g= $(452 + 21
g)
(b)
If
g = $4,
Cost of the mobile phone
= 452 + 21 x 4
= 452 + 84
= $536
Answer(s): (a) $(452 + 21
g) or $(21
g + 452); (b) $536
