For any positive integer a, let *a* denote the smallest prime factor

Question

Hello Guys,

Help me solve the following question:

For any positive integer a, let *a* denote the smallest prime factor of a. Which of the following is equal to *35* ?

a) *10*
b) *15*
c) *45*
d) *55*
e) *75*

I didn't get a hang of this question.

Thank you,

GR

BeingHan · Answer

The answer is D 55
*35* will denote the smallest prime factor of 35, which happens to be 5.
Similarly*55* will denote the smallest prime factor of 55, which is equal to 5

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pushpitkc · Answer

Hi  greatchap ,
As *a* denotes the smallest prime factor of a. 
In order to find out the value of *35*, we need to prime factorize 35 which is 5*7
*35* is nothing but 5 because the smaller prime factor of 35 is 5.

The answer options when prime factorized :
a) 10 = 2*5
b) 15 = 3*5
c) 45 = 3^2*5
d) 55 = 5*11
e) 75 = 3*5^2

Of these options Option D(55) has the same smallest prime factor as *35*

Hope that helps!

JeffTargetTestPrep · Answer

Since 35 = 5 x 7, the smallest prime factor of 35 is 5 and *35* = 5.

Looking at our answer choice, the only choice whose smallest prime factor is 5 is 55 because 5 x 11 = 55.

Answer: D

ManifestDreamMBA · Answer

35 = 5*7
*35* = 5
For any other value to have the smallest prime factor as 5, it cannot have 2 and 3 as factor. 
So anything even or multiple of 3 is out. Eliminates A,B,C and E.
Answer *55*

For any positive integer a, let a denote the smallest prime factor

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