Advertisements
Advertisements
Question
Find the term t15 of an A.P. : 4, 9, 14, …………..
Advertisements
Solution
We need to find the 15th term of the A.P., 4, 9, 14
Here, the initial term is, a = 4.
Common difference = 14 - 9 = 9 - 4 = 5
The general term of an A.P is given by the formula,
tn = a + (n - 1)d
t15 = 4 + (15 - 1) × 5
t15 = 4 + 14 × 5
t15 = 4 + 70
t15 = 74
RELATED QUESTIONS
Find the sum of the following arithmetic series:
(–5) + (–8) + (–11) + ... + (–230)
Find the 19th term of the following A.P.:
7, 13, 19, 25, ...
Find the 27th term of the following A.P.
9, 4, –1, –6, –11,...
Six year before, the age of mother was equal to the square of her son's age. Three year hence, her age will be thrice the age of her son then. Find the present ages of the mother and son.
Select the correct alternative and write it.
If a share is at premium, then -
If the sum of first n terms of an AP is n2, then find its 10th term.
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 tn if a = 20 and d = 3.
Decide whether the given sequence 24, 17, 10, 3,...... is an A.P.? If yes find its common term (tn).
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.
If tn = 2n – 5 is the nth term of an A.P., then find its first five terms.
The nth term of an A.P. 5, 8, 11, 14,...... is 68. Find n = ?
In an A.P. if the sum of third and seventh term is zero. Find its 5th term.
Write the next two terms of the A.P.: `sqrt(27), sqrt(48), sqrt(75)`......
