Question

Between the numbers 2 and 20, 8 means are inserted, then their sum is
A) 88
B) 44
C) 176
D) None of these

Answer 1

Hint: There's a Specific formula to find the sum of the means i.e., \[\dfrac{n}{2}(a + b)\] where n is the total number of means inserted and a and b are the upper limit and lower limit of the range given to us.
Complete step by step answer:
Here we know that \[\dfrac{n}{2}(a + b)\] where n is the total number of means inserted and a and b are the upper limit and lower limit of the range given to us.
 So let us try to solve the question
\[\begin{array}{l}
n = 8\\
a = 2\\
b = 20
\end{array}\]
Let us put all these in the formula known to us, We will get the required result as
\[\begin{array}{l}
 = \dfrac{n}{2}(a + b)\\
 = \dfrac{8}{2}(2 + 20)\\
 = 4 \times 22\\
 = 88
\end{array}\]
Therefore option A is correct.

Note: Here means is arithmetic mean and also this question can be tackled in a different way first find the sum of all means in the range between 2 to 20 then subtract it with (20+2). You will find the same result.