Question

Average of 12 numbers is 55, sum of first 3 numbers is 85. Then find the 4th number?​

Answer 1

Answer:

Sum of the 3 numbers = 85

Average of 12 numbers =55

Let us assume that the fourth number is x.

Now,

As average is given,

Sum =sum of observations /number of observations

or, 55 = 85 +x /4

or,  220 =85 +x

or,  x = 220-85

or, x=   135

Therefore, the fourth number is 135

Step-by-step explanation:

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