Is – 150 a term of AP: 11, 8, 5, 2?

see full answer

Your Exam Success, Personally Taken Care Of

1:1 expert mentors customize learning to your strength and weaknesses – so you score higher in school , IIT JEE and NEET entrance exams.

An Intiative by Sri Chaitanya

Yes

Data Insufficient

Can’t Say

answer is A.

(Unlock A.I Detailed Solution for FREE)

Best Courses for You

JEE

NEET

Foundation JEE

Foundation NEET

CBSE

Detailed Solution

Let – 150 be the nth term of the AP is 11, 8, 5, 2.
The formula for nth term of an AP is given as:
an = a+(n−1)d here,
nth term (an) = - 150
First term (a) = 11
Common difference (d) = - 3 (∵8−11=−3,5−8=−3)
Position of the nth term = n
Substituting the values,
⇒ −150 = 11+(n−1)(−3)
⇒ −3(n−1) = −150−11
⇒ −3(n−1) = −161
⇒ −3n+3 = −161
⇒ −3n = −161−3
⇒ −3n = −164
⇒ n

= - \frac{164}{- 3}

⇒ n = 54.66
The value of n obtained is a decimal number and not an integer showing that there can be no possible position for this nth term.
Therefore, – 150 is not a term of the given AP and the correct option is 1.

Watch 3-min video & get full concept clarity