Advertisements
Advertisements
प्रश्न
If a = 6 and d = 10, then find S10
उत्तर
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
संबंधित प्रश्न
The first and the last terms of an AP are 7 and 49 respectively. If sum of all its terms is 420, find its common difference.
If Sn denotes the sum of first n terms of an A.P., prove that S30 = 3[S20 − S10]
Find the sum of all natural numbers between 250 and 1000 which are exactly divisible by 3
An A.P. consists of 50 terms of which 3rd term is 12 and the last term is 106. Find the 29th term of the A.P.
Find the sum of the following APs.
−37, −33, −29, …, to 12 terms.
Find the sum given below:
`7 + 10 1/2 + 14 + ... + 84`
Find the sum of the first 15 terms of each of the following sequences having the nth term as
`a_n = 3 + 4n`
The first term of an A.P. is 5, the last term is 45 and the sum of its terms is 1000. Find the number of terms and the common difference of the A.P.
If the 8th term of an A.P. is 37 and the 15th term is 15 more than the 12th term, find the A.P. Also, find the sum of first 20 terms of A.P.
The 8th term of an AP is zero. Prove that its 38th term is triple its 18th term.
The 4th term of an AP is 11. The sum of the 5th and 7th terms of this AP is 34. Find its common difference
Write the next term of the AP `sqrt(2) , sqrt(8) , sqrt(18),.........`
Q.7
Find the sum of all members from 50 to 250 which divisible by 6 and find t13.
The sum of first six terms of an arithmetic progression is 42. The ratio of the 10th term to the 30th term is `(1)/(3)`. Calculate the first and the thirteenth term.
In a ‘Mahila Bachat Gat’, Sharvari invested ₹ 2 on first day, ₹ 4 on second day and ₹ 6 on third day. If she saves like this, then what would be her total savings in the month of February 2010?
If the sum of three numbers in an A.P. is 9 and their product is 24, then numbers are ______.
Find the sum of first 'n' even natural numbers.
The nth term of an A.P. is 6n + 4. The sum of its first 2 terms is ______.