If the average (arithmetic mean) of a, b, c, 5, and 6 is 6, what is th

Question

If the average (arithmetic mean) of a, b, c, 5, and 6 is 6, what is the average of a, b, c, and 13?

(A) 8
(B) 8.5
(C) 9
(D) 9.5
(E) It cannot be determined from the information given.

raks85 · Answer

a+b+c+5+6=5*6
-> a+b+c = 19
-> a+b+c+13 = 32
-> (a+b+c+13)/ 4 = 32/4 = 8, hence option (A)

mahi816 · Answer

very basic question.

(a+b+c+5+6)/5=6, so a+b+c=19.

(a+b+c+13)/4=(19+13)/4=8

ANS.A

PKN · Answer

Given, a+b+c+5+6=5*6=30
Or, a+b+c+5+6+2=30+2=32
Or,  \frac{a+b+c+13}{4}=\frac{32}{4}=8 
Or, average of a, b, c, and 13 is 8

Ans. (A)

KSBGC · Answer

\frac{a + b + c + d + 5 + 6}{5 = 6}

a + b + c + d + 11 = 30

a + b + c = 19

a + b + c + 13 / 4

\frac{19 + 13}{4}

=  \frac{32}{4}

= 8

The best answer is A.

Abhishek009 · Answer

a + b + c + 5 + 6 = 30

So,  a + b + c = 19

So, the average of a, b, c, and 13 =  \frac{19 + 13}{4} = 8  Answer must be (A)

JeffTargetTestPrep · Answer

We can create the equation:

(a + b + c + 5 + 6)/5 = 6

a + b + c + 11 = 30

a + b + c = 19

So the average of a, b, c, and 13 is:

(a + b + c + 13)/4

(19 + 13)/4

32/4 = 8

Answer: A

BrushMyQuant · Answer

Theory

➡ Average = Sum of all the Values / Total Number of Values

The average (arithmetic mean) of a, b, c, 5, and 6 is 6

Average =  \frac{Sum}{5}  =  \frac{a + b + c + 5 + 6 }{5}  =  \frac{a + b + c + 11}{5}  = 6 (given)
a + b + c + 11 = 6*5 = 30
=> a + b + c = 30 - 11 = 19

The average of a, b, c, and 13

Average =  \frac{Sum}{4}  =  \frac{a + b + c + 13 }{4}  =  \frac{19 + 13}{4}  =  \frac{32}{4}  = 8

So,  Answer will be A .
Hope it helps!

Watch the following video to Learn the Basics of Statistics

https://www.youtube.com/watch?v=Cvy_HHw4KIs

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If the average (arithmetic mean) of a, b, c, 5, and 6 is 6, what is th

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