1
1
22nd term of the A.P.: $\frac{3}{2}, \frac{1}{2}, \frac{-1}{2}, \frac{-3}{2}, ........ $ is
22nd term of the A.P.: $\frac{3}{2}, \frac{1}{2}, \frac{-1}{2}, \frac{-3}{2}, ........ $ is
a) $\frac{45}{2}$
b) $-9$
c) $\frac{-39}{2}$
d) $-21$
This Question has 1 answers.
Given A.P.: $ \displaystyle \frac{3}{2}, \frac{1}{2}, \frac{-1}{2}, \frac{-3}{2}, \dots $
First term: $ \displaystyle a = \frac{3}{2} $
Common difference:
$ \displaystyle d = \frac{1}{2} - \frac{3}{2} = -1 $
The general formula for the $ \displaystyle n $th term of an A.P. is:
$ \displaystyle a_n = a + (n-1) d $
Substituting $ \displaystyle n = 22 $:
$ \displaystyle a_{22} = \frac{3}{2} + (22-1)(-1) $
$ \displaystyle = \frac{3}{2} + 21(-1) $
$ \displaystyle = \frac{3}{2} - 21 $
$ \displaystyle = \frac{3}{2} - \frac{42}{2} $
$ \displaystyle = \frac{-39}{2} $
Thus, the 22nd term is $ \displaystyle \frac{-39}{2} $.
First term: $ \displaystyle a = \frac{3}{2} $
Common difference:
$ \displaystyle d = \frac{1}{2} - \frac{3}{2} = -1 $
The general formula for the $ \displaystyle n $th term of an A.P. is:
$ \displaystyle a_n = a + (n-1) d $
Substituting $ \displaystyle n = 22 $:
$ \displaystyle a_{22} = \frac{3}{2} + (22-1)(-1) $
$ \displaystyle = \frac{3}{2} + 21(-1) $
$ \displaystyle = \frac{3}{2} - 21 $
$ \displaystyle = \frac{3}{2} - \frac{42}{2} $
$ \displaystyle = \frac{-39}{2} $
Thus, the 22nd term is $ \displaystyle \frac{-39}{2} $.
Similar Questions
- The letters A, B, C, D, E, F and G not necessarily in that order, stand for seven consecutive integers from 1 to 10, D is 3 less than A, B is the middle term. F is as much less than B as C is greater than D, G is greater than F.
- If we took the 500 people attending a school in New York City, divided them by gender, and then took a random sample of the males and a random sampling of the females, the variable on which we would divide the population is called the ........
- Direction: Each question below is followed by two statements I and II. You have to determine whether the data given is sufficient for answering the question. You should use the data and your knowledge of mathematics to choose the best possible answer. Ho
- Greg Beck of Quality Market Research tells placement student John to go out and select for personal interview ten men and ten women. Greg is using ........ sampling for this phase of the research.
- If the 10th term of the sequence a, a - b, a -2b, a -3b, .... is 20 and the 20th term is 10,then the xth term of the series is