Latest Infosys Aptitude Question SOLUTION: Which one of the following is not a prime number? 31 61 71 91

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(#M40005993) INFOSYS Numerical Ability question infosys latest puzzle Keep an EYE

Which one of the following is not a prime number?
31
61
71
91

Asked In Infosys (12 years ago)

Unsolved Read Solution (10)

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Read Solution (10) :

Sheetal  (12 years ago)

91 is not a prime number as 91 = 13*7

Is this solution Helpfull? Yes (9) | No (1)  

Rahul Rathod  (9 years ago)

non prime number among options 31,61,71,91 is 91

Is this solution Helpfull? Yes (2) | No (1)  

vineesha p  (9 years ago)

we check whether a no is prime or not by checking its divisibility with:
if a no

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Chirag Ranjan Lahiri  (9 years ago)

Simple, as 13 * 7 = 91, so 91 is the correct number.

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Arti agarwal  (9 years ago)

sqrt(91)=approx 9.x so we take 9 prime no. less than 9 are 2,3,5,7 and 91 is divisible by 7 so 91 is not prime number.

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Karthick  (8 years ago)

n^2 > number to be find.
where n is the highest square possible value nearest to the number
1. For 31,
6^2 > 31. prime number below 6 are 2,3,5. If 31 is divide my any one of these number, then it is not a prime number.
4. For 91
11^2 >91. Prime numbers below 11 are 2,3,5,7,9.
91 can be divided by 7. so it is not a prime number.

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Rajasekhar  (8 years ago)

91
HERE 91 IS NOT A PRIME NUMBER.BECAUSE,13*7=91 SO,91 IS NOT A PRIME NUMBER..

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Sparsh Shukla  (7 years ago)

91, because it is divisible by 7

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Uma Narendra Pavan Gunda  (5 years ago)

91 is a multiple of 7. so, it is not a prime number

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Aazam shaik  (5 years ago)

91
Since it is a multiple of 13 as 13×7=91

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