Latest Elitmus Aptitude Question SOLUTION: How many nos from 1 to 100 have prime no of factors? i)25,ii)29,iii)32,iv)33

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(#M40018213) ELITMUS Numerical Ability question Factors Keep an EYE

How many nos from 1 to 100 have prime no of factors?
i)25,ii)29,iii)32,iv)33

Asked In Elitmus Satyaranjan (11 years ago)

Unsolved Read Solution (14)

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Satyaranjan  (11 years ago)

Answer is 32.
As per the Question we should find out the nos which have no of factors=prime no(the factors may be prime or not)
There are 25 prime nos which have only 2(Prime) factors.
And the squares :4,9,16,25,49,64,81 have also prime no of factors.
So total=25+7=32

Is this solution Helpfull? Yes (41) | No (12)  

P.Someshwar Reddy  (11 years ago)

Answer is 33
As we know the total no. of Prime numbers between 1 and 100 are 25 and they have only two numbers as their factors.
and there are squares like 4,9,16,25,49,64,81 and also 100 is included because in the question it is given as 1 to 100 but not as in between 1 to 100
so total 25+8=33

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Satyaranjan  (11 years ago)

16 has factors 1,2,4,8,16=5 no of factors and 5 is a prime no.You can check others also.

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Nishant Gupta  (11 years ago)

Answer is 25
Because Prime nos b/w 1-100 is 25 and questions says that factors of prime no is prime so only prime nos considered b/w 1-100.

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mahesh guntumadugu  (11 years ago)

total 25 ...2,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73,79,83,89,97.

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Karthik G Aradhya  (11 years ago)

33
there a 25 prime numbers less than 100 and 8 squares less than 100 with prime factors
25+7

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mahesh guntumadugu  (11 years ago)

16,64,81 numbers having multiple factors..ans is 29

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harshavi  (8 years ago)

as we know the no of prime num between 1 to 100 is 25.
we also know the formula to find no of factors.
is if no of the format 2^x*3^y.
then no of factors is (x+1)(y+1).
like wise if we need to find the num with prime factors we need to verify for prime powers 2,3,5,7.
for case 2-->2^n such that (n+1) is prime.it n needs to be 1,2,4,6.thus we get 4,16,64
for case 3 we get 9,81
for case 5 we get 25
for case 7 we get 49
total 25+7=33 values

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Karthik G Aradhya  (11 years ago)

sry 27+8=33

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Anjali Sadhukhan  (8 years ago)

33 is the ans.

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Ramesh Sriram  (7 years ago)

25 prime numbers are there

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KUMAR HARSH  (7 years ago)

i think @MAHESH GUNTUMADUGU is right

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Shalu  (7 years ago)

33 is right ans

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Digesh Singh Bisht  (1 year ago)

25 primes and (4,9,16,25,49,64,81) = total 32 ans

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