M4maths Previous Puzzles

10 May 2011 Average

The sum of 5 positive integers is 16. If we subtract the greatest integer from the sum, the average of remaining 4 integers would be 2.5. In the similar manner if we subtract the least one, the average of remaining 4 integers would be 3.75. The average of middle 3 integers will be

OPtion

1) 6
2) 5
3) 9
4) 2
5) 8
6) 7
7) 1
8) 3
9) 10
10) 4

Solution

2.5 * 4 = 10 so the greatest number is 16 -10 = 6
3.75 * 4 = 15 so the least number is 16 - 15 = 1
thus the sum of middle 3 numbers = 16 - 6 - 1 = 9
average = 9/3 = 3

Correct Option: 8 Best Solution (6)

Dr.Dipin Singh   14 years AGO

The sum of 5 positive integers is 16. If we subtract the greatest integer from the sum, the average of remaining 4 integers would be 2.5 and hence sum of remaining 4 integers would be 4*2.5=10.So the greatest integer is 16-10=6.In the similar manner if we subtract the least one, the average of remaining 4 integers would be 3.75 and their sum is 4*3.75=15. Then smallest integer will be 16-15=1. The sum of middle 3 integers will be 16-6-1=9. The average of middle 3 integers will be 9/3=3.. option 8

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Sahil   14 years AGO

The sum of 5 positive integers is 16.
sum of smallest 4 nos= 2.5x4=10
largest no=16-10=6
sum of largest 4 nos= 3.75x4=15
smallest no=16-15=1.
sum of middle 3 integers = 16-6-1=9
Average of middle 3 nos= 9/3=3

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Karthick Babu   14 years AGO

Let us take a,b,c,d,e be five integers and also take a is greatest int and e is least int.
a+b+c+d+e=16.
b+c+d+e=2.5*4=10.--->(1)
a+b+c+d=3.75*4=15.--->(2)
add (1) & (2) we get,
a+b+b+c+c+d+d+e=25
16+b+c+d=25
b+c+d=9
The avg is (b+c+d)/3=3
So the ans is 3(Option 8)

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Balakumaran N.A   14 years AGO

let take, a+b+c+d+e=16. If a is big,
then b+c+d+e=2.5*4 ;and If e is small,
then a+b+c+d=3.75*4;
so, we can get e=1;a=6; then,
6+b+c+d+1=16 => b+c+d=9 and avg is 3;

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KALPANA G   14 years AGO

take the 5 integers are a,b,c,d,e.
given a+b+c+d+e=16
and (a+b+c+d)/4=2.5
(b+c+d+e)/4=3.75
adding these two, (a+b+c+d+e+b+c+d)/4=6.25
==> 16+(b+c+d)=25
==>b+c+d=9
==>(b+c+d)/3=3, average of middle three integers

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Kalidas   14 years AGO

The sum of middle 3 integers =16-6-1=9

The average of middle 3 integers will be 9/3=3.

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