Which term of the $AP: 3, 15, 27, 39, \ldots$ will be $132$ more than its $54^{th}$ term?

Vedclass pdf generator app on play store
Vedclass iOS app on app store
(65) Given $A.P.$ is $3, 15, 27, 39, \ldots$
First term $a = 3$.
Common difference $d = 15 - 3 = 12$.
The $54^{th}$ term is given by $a_{54} = a + (54 - 1)d$.
$a_{54} = 3 + 53 \times 12 = 3 + 636 = 639$.
We need to find the term $a_n$ such that $a_n = a_{54} + 132$.
$a_n = 639 + 132 = 771$.
Using the formula $a_n = a + (n - 1)d$:
$771 = 3 + (n - 1)12$.
$768 = (n - 1)12$.
$n - 1 = \frac{768}{12} = 64$.
$n = 65$.
Alternatively,the difference between the $n^{th}$ term and the $54^{th}$ term is $(n - 54)d = 132$.
$(n - 54)12 = 132$.
$n - 54 = 11$.
$n = 65$.

Explore More

Similar Questions

$A$ ladder has rungs $25 \, cm$ apart. (see Figure). The rungs decrease uniformly in length from $45 \, cm$ at the bottom to $25 \, cm$ at the top. If the top and the bottom rungs are $2 \frac{1}{2} \, m$ apart,what is the length of the wood required for the rungs?

Difficult
View Solution

Find the sum of the first $24$ terms of the list of numbers whose $n^{th}$ term is given by $a_{n} = 3 + 2n$.

$1^{2}, 3^{2}, 5^{2}, 7^{2}, \ldots$ are $APs$? If they form an $AP,$ find the common difference $d$ and write three more terms.

Ramkali saved ₹ $5$ in the first week of a year and then increased her weekly savings by ₹ $1.75$. If in the $n$-th week,her weekly savings become ₹ $20.75$,find $n$.

How many terms of the $AP: 24, 21, 18, \ldots$ must be taken so that their sum is $78$?

Vedclass Products

For Students

Vedclass Test Series

Mock tests in real JEE/NEET style with performance analysis. 5-day free trial.

Start Free Trial
For Teachers

Exam Paper Generator

Generate Set A/B/C/D exam papers from 7.5L+ questions in 2 minutes. 3 chapters free.

Try Free
For Institutes

Online Exam Module

Live online exams with unlimited students, 360° analytics & white-label branding.

See Demo