Nancy shopped at four department stores and spent an average of $80

Question

Nancy shopped at four department stores and spent an average of $80 per store. If she wants to average no more than $70 per store over a total of six stores, what is the most she can average at the two remaining stores?

Sum/4 = 80
Sum=80*4=320

(Sum+x+x)/6 = 70
320+2x= 420
2x=420-320
2x=100
x=50

B

A $40
B $50
C $55
D $65
E $70

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kb26 · Answer

40$ extra spent on the first 4 need to be compensated on the last 2. So, avg becomes 70 - (40/2) = 50$ Ans B.

Napier · Answer

Average amount for the first 4 shops = 80$
Total amount spend for the first 4 shops =  4 * 80  =320$
Average amount she can pay for 6 shops = 70$
Total amount = 70 * 6 =420$
Average amount she should pay on the last two shops for achieveing her 70$ average=  \frac{420-320}{2}  = 50$

MakB · Answer

Average =  \frac{Sum}{no. of observations}

Sum = 80x4 = 320

New average needed = 70
New observations (shops) = 6
So,

\frac{320 + x }{ 6}  = 70

320+x = 420

x= 100

So for last 2 shops, 100$ will be the total spent.
This averages to 50$ per shop.
 Hence, B

Kevi · Answer

Nancy shopped at four department stores and spent an average of $80 per store. If she wants to average no more than $70 per store over a total of six stores, what is the most she can average at the two remaining stores?

Sum/4 = 80
Sum=80*4=320

(Sum+x+x)/6 = 70
320+2x= 420
2x=420-320
2x=100
x=50

B

Sum/4 = 80 
Sum=80*4=320

(Sum+x+x)/6 = 70 
320+2x= 420
2x=420-320 
2x=100
x=50

B

Nancy shopped at four department stores and spent an average of $80

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­Nancy shopped at four department stores and spent an average of $80

Prep Toolkit

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Nancy shopped at four department stores and spent an average of $80