Question

The average of 4 consecutive Natural

number is 21.5. What will be the 4th number ​

Answer 1

Step-by-step explanation:

Let the 1st consecutive number = X

Sum of all consecutive numbers = X + X+1 + X+2 + X+3

Average = (4X+6)/4

21.5 = (4X+6)/4

21.5×4 = 4X+6

86 = 4X+6

80 =4X

X = 20

4th Consecutive Number = X+3

=23

Answer 2

Answer

Average is the sum of the data values divided by the total number of data values.

Given that, average of 5 consecutive natural numbers is m

Let the 5 consecutive natural be (x−2),(x−1),x,(x+1),(x+2)

Therefore, average is

5

(x−2)+(x−1)+x+(x+1)+(x+2)

⟹m=

5

5x

⟹x=m -------(1)

Given that next three natural numbers are included. Therefore, the next three natural numbers will be (x+3),(x+4),(x+5)

Therefore, the average of all the 8 numbers

=

8

(x−2)+(x−1)+x+(x+1)+(x+2)+(x+3)+(x+4)+(x+5)

=

8

8x+12

=x+

8

12

=m+1.5 (from (1))

Therefore the average of the 8 numbers is 1.5 more than m