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

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.