Math Questions-PLEASE HELP!!!?

Question

1. What is the prime factorization of 330?
2. Find two factors of 28 with a sum of 11?
3.What is the greatest common factor for 36,72 &144
4. What are the prime numbers of 55 & 75?
5. Change 58/7 to a mixed or whole number?

Answer 1

(1) Approach factoring large numbers by first dividing them into smaller numbers which are easier to think about.

For example, in prime-factoring 330, think of it as 33 x 10, and then prime-factor the 33 and the 10:

330 = 33 x 10
33 = 3 x 11, 10 = 2 x 5
So, the prime factorization of 330 is (3 x 11) x (2 x 5), which = 2 x 3 x 5 x 11

For the rest, I won't actually give you the answers but I'll show you how to work them out for yourself:

(2) Work out all the possible factors of 28 (hint: you only need to go up to half of the number you are factoring, or 14 in this case, because going beyond that just produces "mirror images" of factorizations which you have already found). Two of these factors when added together will equal 11. Notice that the question does not say "... two PRIME factors..." because one of them is going to be a compound factor (a prime times a prime).

(3) Start by prime-factoring each of these numbers -- all three numbers will have at least one "2" as a factor, find out what ELSE they all have as a factor and you will have your answer (144, being a large number, should be looked at as 12 x 12, see answer #1).

For example, if the numbers were 40, 60, and 140 they would prime-factor to:
40 = 2 x 2 x 2 x 5
60 = 2 x 2 x 3 x 5
140 = 2 x 2 x 5 x 7
There is a "2 x 2" and a "5" in each of these. Therefore, "2 x 2 x 5" ( = 20) is the greatest common factor. You can't use the third "2" in the first list because the others don't have a third "2." Yopu also can't use the "7" in the last one because it does not appear in the first two lists.

(4) I assume this is supposed to say "What are the prime factors [not numbers] of 55 and 75"? Again, something should jump out at you right away, namely that these are both multiples of 5. The forst is 5 x 11, and the second is 5 x 15. One of those needs to be prime-factored a bit further to get your answer.

(5) To convert this to a mixed or whole number, first divide the top number (numerator) by the bottom number (the denominator). If the result comes out a whole number, so that there is no remainder, then you have your answer. But if not, then you have the first part of the mixed number and the remainder (the second part) is expressed by showing the remainder divided by the denominator.

For example, if the question were "change 60/7 to a mixed or whole number" the way to do it would be:
(A) 60 divided by 7 equals 8 with a remainder of 4.
(B) The first part of the number is 8
(C) the second part of the number (remainder of 4) is 4/7
(D) The answer would be 8 and 4/7.

If doing this by calculator, you do it a little bit differently:
(A) 60 divided by 7 equals 8.5714285....
(B) The first part of the number is 8
(C) Multiply that 8 by the denominator: 8 x 7 = 56
(D) Subtract this from the original numerator (60 - 56 = 4)
(E) The second part of the number is this result divided by the denominator: 4/7
(F) The answer would be 8 and 4/7.

Answer 2

Number One:
330
^
165 2
^
5 33
^
11 3

11 x 5 x 3 x 2

Number Two:
28
^
7 4
7 x 4

For Number Three and Four...try to do these on your own using the factor tree as shown above. Just keep breaking down the numbers until you can't break them down anymore.

Number Five:

How many times can 7 go into 58? If you are not sure start by multiplying 7 by different numbers until you get a number close to 58. For example:

7 x 5 = 35
7 x 6 = 4
7 x 7 = 49
7 x 8 = 56 Since 56 is very close to 58 we know 7 goes into 58 eight times. Therefore the the whole number in the mixed number will be 8.

We know the denominator of the fraction will automatically still be 7. To figure out the numerator or the number on top, subtract 56 from 58 or 58-56 which will equal 2 (the numerator)

Thus, the answer is 8 2/7.

To check this answer multiply the denominator by the whole number and add the numerator and place it all over 7. The answer is 58/7 so you know you have done the mixed number correctly.

Answer 3

1) 11
11 x 30 = 330
2) 4 x 7 = 28
4+7=11
3) 12 x 3 = 36
12 x 6 = 72
12 x 12 = 144
4) 5 x 11 = 55
5 x 15 = 75
5) 58/7 = 8.2857
58/7 = 56(2/7)

Answer 4

1) 11(33)=330
2) 4(7)=28
3) 36*2=72 & 36*4=144
4) the prime numbers of 55 is 11 & 5.===> 11(5)=55
5) 58/7=7*8+2=8+2/7

Answer 5

1.
11 x 5 x 3 x 2

2.
7, 11

3.
12

4.
59, 61, 67, 71, 73 or 5 x 11 and 5 x 5 x 3

5.
8 2/7

Don't have people do your homework on the web, you need to learn how to think.

However, since homework is a way for teachers with oversized classes force learning, which doesn't work and makes people grow up too fast, Ill help you out this one time.

Answer 6

1. 2x3x5x11

2. 7 and 4

3. 36

4. ?

5. 8 2/7

Answer 7

actually #3 is 36
36*1=36
36*2=72
36*4=144

Answer 8

what grade are you in? these sound like elementary Questions.