Advertisements
Advertisements
Question
If a = 6 and d = 10, then find S10
Advertisements
Solution
a = 6 and d = 10 ......[Given]
Since Sn = `"n"/2[2"a" + ("n" - 1)"d"]`,
S10 = `10/2 [2(6) + (10 - 1)(10)]`
= 5[12 + 9 (10)]
= 5(12 + 90)
= 5(102)
= 510
RELATED QUESTIONS
The first and the last terms of an AP are 8 and 65 respectively. If the sum of all its terms is 730, find its common difference.
Find the sum of the following arithmetic progressions:
3, 9/2, 6, 15/2, ... to 25 terms
Find the sum of first 51 terms of an A.P. whose 2nd and 3rd terms are 14 and 18 respectively.
Find the middle term of the AP 10, 7, 4, ……., (-62).
Find the sum of two middle most terms of the AP `-4/3, -1 (-2)/3,..., 4 1/3.`
If the ratio of sum of the first m and n terms of an AP is m2 : n2, show that the ratio of its mth and nth terms is (2m − 1) : (2n − 1) ?
In an A.P. sum of three consecutive terms is 27 and their product is 504, find the terms.
(Assume that three consecutive terms in A.P. are a – d, a, a + d).
Find four consecutive terms in an A.P. whose sum is 12 and sum of 3rd and 4th term is 14.
(Assume the four consecutive terms in A.P. are a – d, a, a + d, a +2d)
In an A.P. the 10th term is 46 sum of the 5th and 7th term is 52. Find the A.P.
What is the sum of first 10 terms of the A. P. 15,10,5,........?
Find the sum of the first 15 terms of each of the following sequences having nth term as xn = 6 − n .
In an A.P., the sum of first ten terms is −150 and the sum of its next ten terms is −550. Find the A.P.
Write 5th term from the end of the A.P. 3, 5, 7, 9, ..., 201.
If \[\frac{1}{x + 2}, \frac{1}{x + 3}, \frac{1}{x + 5}\] are in A.P. Then, x =
The sum of first 14 terms of an A.P. is 1050 and its 14th term is 140. Find the 20th term.
If the third term of an A.P. is 1 and 6th term is – 11, find the sum of its first 32 terms.
In an A.P., the sum of its first n terms is 6n – n². Find is 25th term.
Find the sum of odd natural numbers from 1 to 101
The famous mathematician associated with finding the sum of the first 100 natural numbers is ______.
Jaspal Singh repays his total loan of Rs. 118000 by paying every month starting with the first instalment of Rs. 1000. If he increases the instalment by Rs. 100 every month, what amount will be paid by him in the 30th instalment? What amount of loan does he still have to pay after the 30th instalment?
