Chapter 9 Class 11 Sequences and Series | Extra Questions
Q1. Insert five numbers between 8 and 26 such that the resulting sequence is an A.P.
Ans: 11, 14, 17, 20, 23.
Q2. Show that the sum of (m+n)th and (m–n)th terms of an A.P. is equal to twice the mth term.
Q3. Find the sum of integers from 1 to 100 that are divisible by 2 or 5.
Q4. Is 309 a term of the AP 11, 17, 23….?
Q5. If the AM between the ath and bth terms of an AP be equal to the AM between the cth and dth term of it then prove that a + b = c + d
Q6. A carpenter was hired to build 192 window frames. The first day he made five frames and each day, thereafter he made two more frames than he made the day before. How many days did it take him to finish the job?
Ans: 12 days