find prime between 40 and 50 so sum of factors of prime+1 is

[scotch]

6TH GRADE WORD PROBLEM: I am a prime number between 40 and 50. If you add 1 to me, the sum of the prime factors of that compostie number is 11. What number am I? :mrgreen:

 

[Loren]

Re: 6TH GRADE WORD PROBLEM

Suppose it said "between 50 and 60" rather than "40 and 50"? This is what I would do.
I would identify the prime numbers btween 50 and 60. They are 53 and 59.

Then I would select the firsr one, 53.
Add 1 to it getting 54.
I would then find the factors of 54 --- 2, 3, 3 and 3.
I would add them and see if their sum = 11.
If they don't I would try the next number.

 

[scotch]

Re: 6TH GRADE WORD PROBLEM

BETWEEN 40 AND 50
PRIME NUMBERS 41,43 AND 47

41+1=42 PRIME FACTORS 2,3,7 = 12
43-1=44 2,11 = 13
47=1 = 48 2,3,

 

[mmm4444bot]

Re: 6TH GRADE WORD PROBLEM

43-1=44 2,11 = 13
47=1 = 48 2,3,

Hi Scotch:

Try listing all of the prime factors. :idea:

Looking at your work for the prime 43, for example, it could be 44 = 2 * 2 * 11, and 2 + 2 + 11 = 15.

The factor of 2 is repeated once because, as you know, 44 is 4 * 11, not 2 * 11.

Cheers,

~ Mark