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Subject :NSO    Class : Class 8

Look at the given pattern.
3, 7, 15, 31, 63, .....
What is the 7th term in the pattern ?
(a) 127
(b) 128
(c) 255
(d) 258


3 4=7,7 (4*2)=15,...63 (32*2)=127. I think this is the pattern, but if that is so then answer does not match!

Ans 1:

Class : Class 9
The answer is Option C that is 255 The difference from 3 to 7 is 4. The different from 7 to 15 is 8. The difference from 15 to 31 is 16. The difference from 31 to 63 is 32. The observation if 4 X 2 = 8, 8 X 2 = 16. Like wise, we can find next ones also. Only 5 are given and we have to find the 7th one. So, let is first find the 6th one. 32 X 2 = 64. So, 63 + 64 = 127. The 6th number is 127. Now, we have to find the 7th one. 64 X 2 = 128. 127 + 128 = 255. That is Option C

Ans 2:

Class : Class 10
Kindly give me the reasoning of the pattern.

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