Maths / Arithmetic Progression / Find The Value of Nth Term when Common Difference, Number of Terms and First Term are Given

QUESTION

Which  term of the AP 1, 5, 9, 13, ......... is 405?

 OPTIONS A. $\dpi{100} 103^r^d$ B. $\dpi{100} 105^t^h$ C. $\dpi{100} 117^t^h$ D. $\dpi{100} 102^n^d$
Right Option : D

EXPLANATION
Explain TypeExplanation Content
Text

For the given AP a = 1, a + d = 5 or d = 4

Let                    $\dpi{100} a_n$  = 405 $\dpi{100} \rightarrow$  a + (n - 1) d = 405

$\dpi{100} \rightarrow$             1 + (n - 1) (4) = 405  $\dpi{100} \rightarrow$  (n - 1) (4) = 404  $\dpi{100} \rightarrow$ n - 1 = 101

$\dpi{100} \rightarrow$                               n = 102

Thus the $\dpi{100} 102^t^h$ term is 405.

View Contents
(Concept based Learning and Testing for [6th - 10th], NTSE, Bank & Govt. Exams)
Self Learning
Testimonials
PARENT RESPONSE c/o Hiya Gupta C/o ABHYAS Academy
9th
My experience with abhyas is very good. It had helped to increase mental ability of my ward.

#### Other Testimonials

Courses We Offer
(Concept based Learning and Testing for [6th - 10th], NTSE, Bank & Govt. Exams)