Problem Solving

Q. The average of 5 consecutive natural numbers is m. If the next three natural numbers are also included, how much more than m will the average of these 8 numbers be?
a) 2 b) 1 c) 1.4 d) 1.5

Joy Shaha wrote:Q. The average of 5 consecutive natural numbers is m. If the next three natural numbers are also included, how much more than m will the average of these 8 numbers be?
a) 2 b) 1 c) 1.4 d) 1.5

Recognize that the average of 5 consecutive numbers is the same as the median, which is 3 higher than the starting number in the list.

Therefore, m = n+3 where n is the starting number.

Now, with 8 numbers, recognize that the average is the average of the 4th and 5th numbers, so

New average = ((n+4)+(n+5))/2 = n + 4.5

Therefore, the difference in the averages is (n + 4.5) - (n+3) = 1.5

Answer is D