In the AP: 10, 5, 0, –5, … the common difference d is equal to 5. Justify whether the above statement is true or false.
In an AP if a = 1, an = 20 and Sn = 399, then n is
(A) 19 (B) 21 (C) 38 (D) 42
The sum of first 16 terms of the AP: 10, 6, 2,… is
(A) –320 (B) 320 (C) –352 (D) –400
If the first term of an AP is –5 and the common difference is 2, then the sum of the first 6 terms is
(A) 0 (B) 5 (C) 6 (D) 15
The famous mathematician associated with finding the sum of the first 100 natu- ral numbers is
(A) Pythagoras (B) Newton (C) Gauss (D) Euclid
The 4th term from the end of the AP: –11, –8, –5, …, 49 is
(A) 37 (B) 40 (C) 43 (D) 58
If 7 times the 7th term of an AP is equal to 11 times its 11th term, then its 18th term will be
(A) 7 (B) 11 (C) 18 (D) 0
Two APs have the same common difference. The first term of one of these is –1 and that of the other is – 8. Then the difference between their 4th terms is
(A) –1 (B) – 8 (C) 7 (D) –9