Elijah saved $9 each day and Vanessa saved $
m more than Elijah each day. After 3 weeks, they were still short of $28 to buy a hard drive.
- How much did the hard drive cost? Express your answer in terms of m.
- If m = $7, how much did the hard drive cost?
(a)
Amount Elijah saved per day = $9
Amount Vanessa saved per day = $(9 +
m)
Total amount both saved per day
= 9 + 9 +
m = $(18 +
m)
Number of days in 3 weeks
= 3 x 7
= 21
Total both saved in 3 weeks
= 21(18 +
m)
= 21 x 18 + 21 x
m = $(378 + 21
m)
Cost of the hard drive
= 378 + 21
m + 28
= 378 + 28 + 21
m= $(406 + 21
m)
(b)
If
m = $7,
Cost of the hard drive
= 406 + 21 x 7
= 406 + 147
= $553
Answer(s): (a) $(406 + 21
m) or $(21
m + 406); (b) $553
