In the following number series, two numbers have been put within brackets. Study the series carefully and select the correct alternative with respect to the series.
0,7,26,63,(124),215,342,(512)
- AThe first bracketed number (from the left) is correct and the second is incorrect.
- BThe first bracketed number (from the left) is incorrect and the second is correct.
- CBoth the bracketed numbers are incorrect.
- DBoth the bracketed numbers are correct.
Solution & Step-by-step Explanation
The pattern of the series follows the rule: n
3
−1, where n=1,2,3,4,5,6,7,8.
1
3
−1=1−1=0
2
3
−1=8−1=7
3
3
−1=27−1=26
4
3
−1=64−1=63
5
3
−1=125−1=124 (First bracketed number is correct)
6
3
−1=216−1=215
7
3
−1=343−1=342
8
3
−1=512−1=511 (Second bracketed number is given as 512, so it is incorrect)
Thus, the first bracketed number is correct and the second is incorrect.
3
−1, where n=1,2,3,4,5,6,7,8.
1
3
−1=1−1=0
2
3
−1=8−1=7
3
3
−1=27−1=26
4
3
−1=64−1=63
5
3
−1=125−1=124 (First bracketed number is correct)
6
3
−1=216−1=215
7
3
−1=343−1=342
8
3
−1=512−1=511 (Second bracketed number is given as 512, so it is incorrect)
Thus, the first bracketed number is correct and the second is incorrect.