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The generated number is a prime number.

Prime_number = Quotient*18 + Remainder

When Prime_number is divided by 18 the remainder must be a number between 0 and 17.

The Remainder can not be 0 because prime numbers greater than 10 are all odd numbers and they can not be a multiple of 18.
The Remainder can not be an even number because prime numbers greater than 10 are all odd numbers and "Quotient*18 + Remainder" would be an even number.
The Remainder can not be a multiple of 3 because "Quotient*18 + Remainder" would be a multiple of 3 and Prime_number would not be a prime number.

6 values for the remaining remainders: 1,5,7,11,13,17

Prime_number = 19 remainder 1
Prime_number = 23 remainder 5
Prime_number = 43 remainder 7
Prime_number = 11 remainder 11
Prime_number = 13 remainder 13
Prime_number = 17 remainder 17

The correct answer is D
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Given in the question: The number is greater than 10 & the number has no factors => number is prime greater than 10
Hence the number can only be odd (only even prime is 2).
=>So the number cannot give an even remainder when divided by 18.
The only odd remainders possible with 18 are 1,3,5,7,9,11,13,15,17 --- 1

Now, 18 = 2*3^2

There can be 2 cases => number has common factors with 18 and not. And as per the question the number cannot have any factors, let alone common with 18. (As the number can then only be 18*N+3*M, which is not prime as divisible by 3.
So, the numbers cannot have any factors common with 18 i.e. relatively prime wo 18.


Hence the remainders can only be = 1,5,7,11,13,17 =>6

Correct Answer => D
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The question needs to find number greater than 10 who has no factors. So, we have to find remainders of prime numbers with no. 18
Prime numbers greater than 10 are 11,13,17,19,23,29,31,37,41,43,47 and so on
Remainders of prime nos by no. 18 are- 11,13,17,1,5,11,13,1,5,7, 11...
Thus there are 1,5,7,11,13,17 remainders which are 6 different nos.

So answer is D
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the answer is 6 given p=7
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Division and remainders are cyclic, i did this the long way:

generated numebr hsa the properties of a prime greater than 10

generated number => 11, 13, 17, 19, 23 , 29
Remainder respectively => 11, 13, 17, 1, 5, 11

therefore answer is 5
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just make cases they will all be prime numbers since no factors as mentioned in the question
start with 11 divided by 18 remainder is 11
13 gives remainder 13
17 gives remainder 17
19 gives 1
23 gives 5
29 gives 11 already there
31 gives 13
37 gives 1
41 gives 5
43 gives 7
53 gives 17 so now we see no new remainders hence answer is 6
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A positive integer .... H .... has no factor bigger than 1 ...and... less than H .... in other words....only factor H has are.... 1 ...and... H ..... so... H is a prime number.....
Now..... program divides H by 18.... so.... remainder [ R ] can possibly be... 1, 2, 3, 4.......17 ......
So...we gotta try to make a prime dats like dis..... [ positive multiple of 18 ] + [ R ] = [ prime ] ......
Now.....18 is even.... so [ any positive multiple of 18 ] + [ any even ] = [ even ] .....
So....any number H... with remainder.... [ R ] = 2, 4, 6, 8, 10, 12, 14, 16 ...will always have factor 2...other than 1 and H .....
So.... possible remainder = 1, 3, 5, 7, 9, 11, 13, 15, 17 .....
But.... factors of 18 [ other than 1 ] = 2, 3, 6, 9, 18 ......

So...any number H ... with a remainder [ R ] that has same factors as factors of 18 [ other than 1 ].... cannot be prime.....

So... remainder with factors of 18 = 3, 9, 15 ..... they all got factor 3 ... which is a factor of 18....
So....3, 9 and 15 cant be remainder [ R ] .....

So.....only possible remainder...... 1, 5, 7, 11, 13, 17 .......so 6 remainder......

! nah id win!
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