Seth saved $11 each day and Sarah saved $
j more than Seth each day. After 5 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 j.
- If j = $17, how much did the mobile phone cost?
(a)
Amount Seth saved per day = $11
Amount Sarah saved per day = $(11 +
j)
Total amount both saved per day
= 11 + 11 +
j = $(22 +
j)
Number of days in 5 weeks
= 5 x 7
= 35
Total both saved in 5 weeks
= 35(22 +
j)
= 35 x 22 + 35 x
j = $(770 + 35
j)
Cost of the mobile phone
= 770 + 35
j + 32
= 770 + 32 + 35
j= $(802 + 35
j)
(b)
If
j = $17,
Cost of the mobile phone
= 802 + 35 x 17
= 802 + 595
= $1397
Answer(s): (a) $(802 + 35
j) or $(35
j + 802); (b) $1397
