Advertisements
Advertisements
Question
Find tn if a = 20 and d = 3.
Advertisements
Solution
tn = a + (n – 1)d
= 20 + (n – 1)3
= 20 + 3n – 3
= 17 + 3n
APPEARS IN
RELATED QUESTIONS
Find the sum of the following arithmetic series:
`7 + 10 1/2 + 14 + ... + 84`
Find the sum of the following arithmetic series:
34 + 32 + 30 + ... + 10
Find the sum of the following arithmetic series:
(–5) + (–8) + (–11) + ... + (–230)
Given Arithmetic Progression 12, 16, 20, 24, . . . Find the 24th term of this progression.
Select the correct alternative and write it.
If a share is at premium, then -
How many multiples of 4 lie between 10 and 205?
If third term and fifth term of an A.P. are 13 and 25 respectively, find its 7th term.
Find t5 if a = 3 and d = –3.
Decide whether the given sequence 24, 17, 10, 3,...... is an A.P.? If yes find its common term (tn).
How many two-digit numbers are divisible by 5?
Activity :- Two-digit numbers divisible by 5 are, 10, 15, 20, ......, 95.
Here, d = 5, therefore this sequence is an A.P.
Here, a = 10, d = 5, tn = 95, n = ?
tn = a + (n – 1) `square`
`square` = 10 + (n – 1) × 5
`square` = (n – 1) × 5
`square` = (n – 1)
Therefore n = `square`
There are `square` two-digit numbers divisible by 5.
Decide whether 301 is term of given sequence 5, 11, 17, 23,.....
Activity :- Here, d = `square`, therefore this sequence is an A.P.
a = 5, d = `square`
Let nth term of this A.P. be 301.
tn = a + (n – 1) `square`
301 = 5 + (n – 1) × `square`
301 = 6n – 1
n = `302/6` = `square`
But n is not positive integer.
Therefore, 301 is `square` the term of sequence 5, 11, 17, 23,......
12, 16, 20, 24,...... Find 25th term of this A.P.
The nth term of an A.P. 5, 8, 11, 14,...... is 68. Find n = ?
If p - 1, p + 3, 3p - 1 are in AP, then p is equal to ______.
Find a and b so that the numbers a, 7, b, 23 are in A.P.
