Questions on Algebra: Divisibility and Prime Numbers answered by real tutors!

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Question 12384: Factor as completely as possible. If not possible to factor then write "Prime
6vw + 18v - 7w - 21=
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Question 12672: Is 187 a prime number.
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Question 12881: what is the smallest number that is divisible dy four different primes?
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Question 12934: All that I have to do is factor this but I think that it is prime. Can someone please tell me if I am right? Thank you.
15x^2+16x+4
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Question 13138: how we can find prime factors of numbers
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Question 13291: How do you figure out the set of numbers when given the GCF? For example, the GCF of two numbers is 850. Neither number is divisible by the other. What is the smallest that these two numbers could be? (This is for a 6th grade math class.) In addition, what guidelines apply when one number is even and the other odd, or both numbers are even/odd. I have been searching the net, but can only find out how to determine the GCF...not the other way around. Thank you!
Click here to see answer by greatscot(1)

Question 13382: if 2x+1 is a multiple of 5,and if 2x+1<100, how many possible values of x are prime numbers
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Question 13478: Could you tell me how to use prime factorization becausem i do not understand how to do it like say for example like 525 how could i turn that in to a prime factorization
Click here to see answer by Earlsdon(6294)

Question 14277: This is the way the teacher wrote down the factorization of 36. (But shouldn't the factorization in the diagram be in the correct factor order of 2x2x3x3 and NOT 3x2x3x2 ?)
Why not:
....MY WAY....................TEACHER'S WAY
......36................................36..........
....../\................................./\.........
...4..X..9..........................6..X..6.........
..../\..../\.........................../\..../\.....
..2x2..X.3x3.......................3x2..X..3x2......
..2X2X3X3...........................2X2X3X3.........
Wouldn't this MY way be correct also?
My son and I are having a problem with diagramming a prime factorization 'tree' (tree is the name given for the drawing). When I diagram a whole number to get its factors, how can I tell what number I should start our with first in the diagram? e.g. MY WAY started with '4'. When I (mom) asked the teacher to send home how to do the tree, her tree started with '2' FIRST (see below). How do I figure out what number the tree diagram should start with underneath the whole number? Is there a specific rule to follow?

Whole number 120 was a problem my son had for homework last night (10/06/05-Thurs). He has a test on this subject Tuesday, 10/11/05 and he still doesn't understand how to do the tree, nor do I know how to help him.

According to a prime factorization chart 120 = 2x2x2x3x5.) Since its very hard to memorize such a listing, how do I know to start my diagram with the number '2'? Why not start with numbers: 120, then underneath, 6 x 20? Then under the 20 would go.... I know know??
PLEASE HELP---A mom who has been out of school since 1974!
Click here to see answer by atif.muhammad(135)

Question 14276: This is the way the teacher wrote down the factorization of 36. (But shouldn't the factorization in the diagram be in the correct factor order of 2x2x3x3 and NOT 3x2x3x2 ?)
Why not:
....MY WAY....................TEACHER'S WAY
......36................................36..........
....../\................................./\.........
...4..X..9..........................6..X..6.........
..../\..../\.........................../\..../\.....
..2x2..X.3x3.......................3x2..X..3x2......
..2X2X3X3...........................2X2X3X3.........
Wouldn't this MY way be correct also?
My son and I are having a problem with diagramming a prime factorization 'tree' (tree is the name given for the drawing). When I diagram a whole number to get its factors, how can I tell what number I should start our with first in the diagram? e.g. MY WAY started with '4'. When I (mom) asked the teacher to send home how to do the tree, her tree started with '2' FIRST (see below). How do I figure out what number the tree diagram should start with underneath the whole number? Is there a specific rule to follow?

Whole number 120 was a problem my son had for homework last night (10/06/05-Thurs). He has a test on this subject Tuesday, 10/11/05 and he still doesn't understand how to do the tree, nor do I know how to help him.

According to a prime factorization chart 120 = 2x2x2x3x5.) Since its very hard to memorize such a listing, how do I know to start my diagram with the number '2'? Why not start with numbers: 120, then underneath, 6 x 20? Then under the 20 would go.... I know know??
PLEASE HELP---A mom who has been out of school since 1974!
Click here to see answer by longjonsilver(2297)

Question 12939: How do you factor this?:

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Question 14801: what is 36 as a product of prime numbers?
Click here to see answer by Earlsdon(6294)

Question 15232: what is the prime factorization in expanded form of
27
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Question 15246: find 3 consecutive even integers such that the sum of the first three is 24 more than the fourth
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Question 15650: what is the number factorization for 36

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Question 10037: If n is an odd integer, which expression always represents an odd integer?
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Question 17726: I'm trying to help my son, 6th grade, with his home work. Could use any help you have to offer.
When multiplying the greatest common factor (GCF) and the least common multiple (LCM) of two numbers the product is always equal to the product of the original two numbers. Why?
Is there an easy to say theorem or "rule" that you could share.
What we came up with: The least commom multiple and the greatest common factor are common to the two numbers. Because they are the smallest and the largest common numbers, when they are multiplied their product is equal to the product of the original two numbers.
Click here to see answer by ivy12003(22)

Question 18104: Need help with 6th grade school project.Other students have to guess the secret number each clue must begin with "I am" and end with "Who am I?"
Example:

Who am I?
I am a composite number, but I look prime.
I am less than 60.
The sum of my digits is 6.
I am divisible by 17.
Who am I?
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Question 18622: what are the prime factors of 120
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Question 18692: What is the smallest prime factor of 1821
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Question 19023: Does there exist a two-digit number 'ab' such that the difference between 'ab' and its reverse 'ba' is a prime number?
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Question 20052: I can't seem to find the prime factorization of 1,120 can you help??????????????????????????????????????????????????????
Click here to see answer by elima(1433)

Question 20179: HOw many distinct prime numbers are factors of 70?
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Question 20179: HOw many distinct prime numbers are factors of 70?
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Question 20317: what are all the prime numbers?
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Question 20525: the number 462 is divisible by which of the following???
a.10 b.6
c.none of these d.5

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Question 20523: the number 64 is divisible by which of the following?
a.6 b.3
c.4 d.5
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Question 20524: choose a tens digit for 2?6 so that the three-digit number is divisible by 6.
a.1 b.3
c.2 d.0
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Question 21039: how do u divide fractions?
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Question 21405: how do I simplify -6-(-3)+ 5-8
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Question 21405: how do I simplify -6-(-3)+ 5-8
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Question 21792: How many factors, including 1, does the product of the first 9 primes divided by the product of the first seven primes have? I think the answer is 7
Click here to see answer by AnlytcPhil(1278)

Question 21796: What is the sum of the digits used to form the integers from 45 to 100 , inclusive?
I thought it was 45+55
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Question 23233: How many subsets of 3 different integers are there whose sum is divisiable by 4?
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Question 18148: Is there any square number besides 9 and 81 that is divisible by 9?
-Thanks!
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Question 25693: Do you have a list of prime numbers up to 1000?
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Question 25223: 26,65 what is the greatest common factor

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Question 27437: What number has only eleven factors?
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Question 27947: factors of 28
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Question 28412: how do you figure out the factors of a number and how do you know if it is prime or not?
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Question 29141: Find the prime factorization of 40
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Question 29141: Find the prime factorization of 40
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Question 29141: Find the prime factorization of 40
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Question 29117: hi. i was assigned to show that there are 43411 consequtive composite numbers. ok, i know that i can do 43411! and if i`ll divide the whole thing by,
say n!+3 I`d be left with the composites. or should i do n! +1 but to start dividing from 43410! instead? thanks.
Click here to see answer by venugopalramana(3286)

Question 30515: -17+r=12
Click here to see answer by checkley71(8403)

Older solutions: 1..45, 46..90, 91..135, 136..180, 181..225, 226..270, 271..315, 316..360, 361..405, 406..450, 451..495, 496..540, 541..585, 586..630, 631..675, 676..720, 721..765, 766..810, 811..855, 856..900, 901..945, 946..990, 991..1035, 1036..1080, 1081..1125, 1126..1170, 1171..1215, 1216..1260, 1261..1305, 1306..1350, 1351..1395, 1396..1440