Question 508292: Christine went shopping and bought each of her nine nephews a gift, either a video costing $14.95 or a CD costing $16.88. She spent $140.34 on gifts. How many videos and CDs did she buy?
Answer by swincher4391(1107)   (Show Source):
You can put this solution on YOUR website! We will set up a system of equations.
Let V = number of videos bought
Let C = number of CDs bought
We know that there are nine nephews in total, so since every nephew got either a video or CD, then the number of videos + number of CDs is also 9.
So V + C = 9.
We also know the cost of each video and CD and how much was spent.
So 14.95V + 16.88C = 140.34
Let's try substitution method here.
Doesn't matter which variable we solve for, so let's just solve for V.
V = 9 - C
So where you see V in the second equation, sub in "9-C"
14.95(9-C) + 16.88C = 140.34
134.55 - 14.95C + 16.88C = 140.34
1.93C = 5.79
C = 3
Sub C = 3 back into either original equation, though I think I know which one you'd find is easier.
V + 3 = 9
V = 6
So we bought 6 videos and 3 CDs. <---- Answer
I hope this helped!
Please e-mail me at onlyyourmathtutor@yahoo.com if this solution did not help, or if you have further questions.
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