Question

Find 9th term from the end of AP 5, 9, 13……………………………, 185.

For what value of ‘k’, k, k-3, 2k+1 are in AP.

How many three digit number are divisible by 11. Find their sum also.

How many integers are between 200 and 600 are divisible by 8. Find their sum also.

Find middle term of the AP 6, 13, 20, …….., 216.

The sum of nth term AP IS 5n2-3n. Find a, d and an.

The sum of first 10 terms is -150 and the sum of next ten terms is -550. Find AP and AN.

 Show that sum of first n even natural numbers is equal to (1+1n )the times the sum of the first n natural odd numbers.

Divide 56 in four equal parts which are in AP such that the ratio of product of its extreme to the product of means is 5:6.

In an AP of 50 terms, the sum of first 10 terms is 210 and the sum of its last 15 terms is 2565. Find AP.

If Sn denotes first n terms of an     AP, prove that S30 = 3( S20-S10).

If the ratio of the sum of first n terms of two AP’s is (7n+ 1): (4n+ 27). Find the ratio of their 9th terms.

An AP consists of 21 terms. The sum of three terms in the middle is 129and last three is 237. Find the AP.

The sum of three numbers in the AP is 12 and sum of their cubes is 288. Find the numbers.

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Answer 1

Answer:

217

Step-by-step explanation:

5,9,13.....185

nth term from the end= l-(n-1)d

l=185,n=9,d=-4

185-(9-1)-4

185+32

217

hope it helps u

Answer 2

Answer:

1. 153

Step-by-step explanation:

a=185

d=a1-a2

=5-9

=-4

a9= a+8d

= 185+8×-4

=185-32

= 153