Mean and median

Question

The number of defects in the first five cars to come through a new production line are 9, 7, 10, 4, and 6, respectively. If the sixth car through the production line has either 3, 7, or 12 defects, for which of theses values does the mean number of defects per car for the first six cars equal the median?

I. 3
II. 7
III. 12

A. I only
B. II only
C. III only
D. I and III only
E. I, II, and III

I. 3
II. 7
III. 12

A. I only
B. II only
C. III only
D. I and III only
E. I, II, and III

kp1811 · Answer

D - I and III only
for 7 we will have mean as 7.16(approx) and median as 7 but for 3 we will have mean and median = 6.5 and for 12 we will have median and mean =8

craigmcdermott · Answer

I disagree with the above response. The answer should be B) II only. 9, 7, 10, 4, and 6 added to 7 = 42. The mean of the set is therefore 7. The Median of the set is also 7. 3 doesn't work and there is only on option that includes 7 and excludes 3. B. Please post OA.

BTW to the response above: I believe that the median must be a number in the set.

BTW to the response above: I believe that the median must be a number in the set.

handsomebrute · Answer

9 + 7 + 10 + 4 + 6 + 7 =  43

As for the median, when the series is even-numbered then the median is the average of the two middle numbers. Answer choice D (I and III) is correct.

kp1811 · Answer

we have set 9, 7, 10, 4, and 6 which is arranged as 4 6 7 9 10   so adding 7 gives us 43   and not 42  . Also mean will be 7.16 and median here will be 7
if we have 3 then the set which we get is 3 4 6 7 9 10   median and mean are both 6.5 here
if we have 12 then the set will be 4 6 7 9 10 12   median and mean both will be 8

Also Median necessarily doesnt need to be a number in the set

Mean and median

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