Target Exam

CUET

Subject

General Test

Chapter

Quantitative Reasoning

Topic

Algebra

Question:

How many terms are there in the A.P. 15,21, 27, ................ , 279 ?

Options:

35

40

45

55

Correct Answer:

45

Explanation:

A.P. = 15,21, 27, ................ , 279

an = a + ( n - 1 )d

a = 1st term , n = number of terms , d = common difference

an = last term

279 = 15 + ( n - 1 )6

264 = ( n - 1 )6

( n - 1 ) = 44

n = 45

The correct answer is option (3) : 45