Average of averages

The number of observations in a group is 40. The average of the first 10 numbers is 4.5 and the average of the remaining 30 members is 3.5. The average of the whole group is

(A) 4 (B) 15/2 (C) 15/4 (D) 6

Answer : (C) 



Explanation : 

= Average  of first members X 10 + Average  of Remaining Members X 30  / 10+30

= 4.5 X 10 + 3.5 X 30 / 40 = 45 +105 /40 =150 /40 = 15 /4

Vinod Kumar

Educator

Prof. Vinod Kumar is an Indian Educator, Motivational Speaker, Naturopathic Practitioner and Entrepreneur . He is the founder of Svtuition... read more »

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