CA Foundation · Quantitative Aptitude · Measures of Central Tendency and Dispersion
If each observation of a data set with mean 48 is first multiplied by 2 and then reduced by 6, what is the mean of the new data?
The new mean is 90. The arithmetic mean follows the same change of scale and origin as the observations, so the new mean is 2 × 48 − 6 = 90.
- A90Correct
- B96
- C84
- D102
Explanation
New mean = 2 × 48 − 6 = 96 − 6 = 90. Option 96 forgets to subtract 6; option 84 wrongly computes 2 × (48 − 6).
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