The average (arithmetic mean) of six numbers is 6. If 3 is subtracted

Question

The average (arithmetic mean) of six numbers is 6. If 3 is subtracted from each of four of the numbers, what is the new average?

A. 1.5
B. 2
C. 3
D. 4
E. 4.5

CounterSniper · Answer

subtracting 3 from each is as good as subtracting 3 from avg 
so 6-3 =3

or else

since am is 6 
sum =36
3 subtracted from each =36-18=18
new average 18/6 =3

Skywalker18 · Answer

Sum of 6 numbers = 6*6 =36
If 3 is subtracted from each of four of the numbers , we subtract 3*4=12 from the total sum
Sum of 6 number after subtracting 3 from each of four of the numbers = 36 - 12 = 24
New average = 24/6 = 4

Answer D

CounterSniper · Answer

.Grr didn't read the question again

Abhishek009 · Answer

Let the numbers be a , b, c , d , e ,f

So, Total of these 6 numbers must be 36

Or, a + b + c + d + e + f = 36

So, 12 must be subtracted from the total sum

i.e a + b + c + d + e + f - 12

Or, 36 - 12 = 24

Hence average of the 6 numbers now is 24/6 =>4

So, Answer will be (D) 4

PS : Ideally I like  Skywalker18  's method and will use the said method.

stonecold · Answer

This is a great Question.
Here is what i did in this Question=>

Mean =\frac{Sum}{#}

Hence Sum = 6*6=36
New sum => 36-(3*4) = 36-12=24
Hence New Mean = 24/6 = 4

Hence D

Abhishek009 · Answer

a + b + c + d + e + f = 30

Or,  6 + 6 + 6 + 6 + 6 + 6 = 30

( 6 - 3 ) + ( 6 - 3 ) + ( 6 - 3 ) + ( 6 - 3 ) + 6 + 6 = 24

So, avergae will be 24/6 = 4
  
Hence, answer will be (D) 4

sangeetar14 · Answer

D

sum/6=6
sum=36
36-12/6=24/6=4

bumpbot · Answer

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The average (arithmetic mean) of six numbers is 6. If 3 is subtracted

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The average (arithmetic mean) of six numbers is 6. If 3 is subtracted

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