Average of any five consecutive odd numbers is 29. If next three consecutive odd numbers are also added then find the new average.
Answer & explanation
Correct answer: option 3
Average of consecutive numbers is always the middle number.
Therefore, ATQ
Five consecutive odd numbers are:
⇒ 25 , 27, 29, 31, 33
IF we add next 3 more consecutive odd numbers, the the numbers are:
⇒ 25 , 27, 29, 31, 33, 35, 37, 39
Then the average of eight numbers will be the middle value = 32
OR
Average = \(\frac{1st\;+\;Last\;number}{2}\) = \(\frac{25\;+\;39}{2}\) = \(\frac{64}{2}\) = 32
Alternate Short cut Method:
*Total consecutive odd/even number added = Increased average*
Hence, if 3 consecutive odd number are added, then the average also increased by 3.
Therefore,
New average = 29 + 3 = 32