Advertisements
Advertisements
प्रश्न
Find the sum of first 20 terms of an A.P. whose first term is 3 and the last term is 57.
उत्तर
Here,
First term, a = 3
Last term, l = 57
n = 20
`S = n/2 (a + I)`
= `20/2 (3 + 57)`
= 10 × 60
= 600
APPEARS IN
संबंधित प्रश्न
If the 3rd and the 9th terms of an AP are 4 and –8 respectively, which term of this AP is zero?
Find the sum of first 15 multiples of 8.
Find the sum of all integers between 50 and 500, which are divisible by 7.
What is the 5th term form the end of the AP 2, 7, 12, …., 47?
Find the sum of the following Aps:
9, 7, 5, 3 … to 14 terms
Choose the correct alternative answer for the following question .
In an A.P. 1st term is 1 and the last term is 20. The sum of all terms is = 399 then n = ....
If the sum of P terms of an A.P. is q and the sum of q terms is p, then the sum of p + q terms will be
Show that a1, a2, a3, … form an A.P. where an is defined as an = 3 + 4n. Also find the sum of first 15 terms.
If the sum of the first m terms of an AP is n and the sum of its n terms is m, then the sum of its (m + n) terms will be ______.
Find the sum of those integers from 1 to 500 which are multiples of 2 as well as of 5.