(solved)Question 13 SSC-CGL 2020 March 3 Shift 2

Question 13
SSC-CGL 2020 Mar 3 Shift 2

Average of 5 consecutive even numbers is X. What will be the average if next 5 consecutive even numbers are also added?

Solution in Short

Average of 5 consecutive even numbers is the middle number. So the middle number is X. When next 5 even are added, there will be two middle numbers: X + 4 and X + 6, whose average is X + 5 answer!

Solution in Detail

Average given = $\displaystyle X$

$\displaystyle \therefore \text{sum} = 5X$

Next five evens are obtained by adding $\displaystyle 10$ to each even. Hence the sum of newly added evens is $\displaystyle 5X + 50$

$\displaystyle \therefore$ Average $\displaystyle = \frac{5X + (5X + 50)}{10}$

$\displaystyle = X + 5\:\underline{Ans}$