Verbal Reasoning - Series Completion - Discussion
Discussion Forum : Series Completion - Section 1 (Q.No. 32)
Directions to Solve
Choose the correct alternative that will continue the same pattern and replace the question mark in the given series.
32.
In the series 3, 9, 15, ...... what will be the 21st term?
Answer: Option
Explanation:
Clearly, 3 + 6 = 9, 9 + 6 = 15,.....
So, the series is an A.P. in which a = 3 and d = 6.
Therefore 21st term = a + (21 - 1) d = a + 20d = 3 + 20 x 6 = 123.
Discussion:
6 comments Page 1 of 1.
Poojasri said:
2 years ago
How did you assume the d value? Please explain.
Samdrup said:
5 years ago
I think the answer is D.
3 x 43 which gives answer 129 which is 21 st term
3x1 = 3
3*3 = 9
3*5 = 15
3*7 = 21
3*9 = 27
3*11 = 33
3*13 = 39
3*15 = 45
And so on.......
Can anyone explain???? Right or wrong
3 x 43 which gives answer 129 which is 21 st term
3x1 = 3
3*3 = 9
3*5 = 15
3*7 = 21
3*9 = 27
3*11 = 33
3*13 = 39
3*15 = 45
And so on.......
Can anyone explain???? Right or wrong
Himanish said:
5 years ago
To find the nth term in an AP we use the formula a+(n-1)*d
Where a is the first term.
n is the number of terms and d is a common difference.
So, here a is 3 n is 21 and d is 6.
So, the answer wud be 123.
Where a is the first term.
n is the number of terms and d is a common difference.
So, here a is 3 n is 21 and d is 6.
So, the answer wud be 123.
(1)
Gayatree Naik said:
5 years ago
I don't understand. Please explain.
Samala sravankumar said:
7 years ago
AP means Arithematic Progression.
(1)
Sriram.V said:
1 decade ago
What is A.P?
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