scotch

10-04-2008, 07:39 PM

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:

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scotch

10-04-2008, 07:39 PM

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

10-04-2008, 07:47 PM

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.

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

10-04-2008, 07:54 PM

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,

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

10-04-2008, 11:12 PM

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 :)

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 :)

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