Over the past 7 weeks, the Smith family had weekly grocery bills of $74, $69, $64, $79, $64, $84, and $77. What was the Smiths' average (arithmetic mean) weekly grocery bill over the 7-week period?
A. $64
B. $70
C. $73
D. $74
E. $85
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BTGmoderatorDC
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Shahrukh_mbabreakspace
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Average= Sum of all bills/7
Sum of all bills = 511
Average = 511/7= 73
Alternatively,
If we assume average to 70 and just look at the distortions and then just edit the answer:
So it becomes(+4-1-6+9-6+14+7)= 21
21/7=3
70+3=73
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B.Tech IIT Roorkee
Sum of all bills = 511
Average = 511/7= 73
Alternatively,
If we assume average to 70 and just look at the distortions and then just edit the answer:
So it becomes(+4-1-6+9-6+14+7)= 21
21/7=3
70+3=73
________________________________________
Shahrukh Moin Khan
QA Mentor at Breakspace
https://www.mbabreakspace.com
PGDM: IIM Calcutta
B.Tech IIT Roorkee
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Brent@GMATPrepNow
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Average = ($74 + $69 + $64 + $79 + $64 + $84 + $77)/7BTGmoderatorDC wrote:Over the past 7 weeks, the Smith family had weekly grocery bills of $74, $69, $64, $79, $64, $84, and $77. What was the Smiths' average (arithmetic mean) weekly grocery bill over the 7-week period?
A. $64
B. $70
C. $73
D. $74
E. $85
= $511/7
= $73
Answer: C
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Scott@TargetTestPrep
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We can determine the average using the formula: average = sum/quantity:BTGmoderatorDC wrote:Over the past 7 weeks, the Smith family had weekly grocery bills of $74, $69, $64, $79, $64, $84, and $77. What was the Smiths' average (arithmetic mean) weekly grocery bill over the 7-week period?
A. $64
B. $70
C. $73
D. $74
E. $85
average = (74 + 69 + 64 + 79 + 64 + 84 + 77)/7 = 511/7 = 73
Answer: C
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regor60
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Just add up the one's digits and keep track the running sum's one's digit.BTGmoderatorDC wrote:Over the past 7 weeks, the Smith family had weekly grocery bills of $74, $69, $64, $79, $64, $84, and $77. What was the Smiths' average (arithmetic mean) weekly grocery bill over the 7-week period?
A. $64
B. $70
C. $73
D. $74
E. $85
Final one's digit is a 1. Since the overall sum is divisible by 7, the average must end in 3. The only answer that meets this is C, 73
