[MOVED] Factoring 45, 41, 54, 48, 100, and 117
- Thread starter Miclee
- Start date
i will do the first one and then you try the rest and let us know how it comes along.
Take 45:
What is the first prime that will divide it?. 2 won't, but 3 will
45/3=15
Will 3 divide into 15?. Yep.
15/3=5
3 won't divide into 5, but the next prime, 5, will.
5/5=1
We're done.
The factors are \(\displaystyle 3\cdot{3}\cdot{5}\)
Take 45:
What is the first prime that will divide it?. 2 won't, but 3 will
45/3=15
Will 3 divide into 15?. Yep.
15/3=5
3 won't divide into 5, but the next prime, 5, will.
5/5=1
We're done.
The factors are \(\displaystyle 3\cdot{3}\cdot{5}\)
D
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If you want the "prime factors" of 45, then you must find every prime number that 45 can be divided by exactly.
For instance, 3 is a prime number that divides into 45. 5 is a prime number that divides 45. Those are the only prime numbers that divide into 45.
However, if you want all the factors of 45, you need to find every whole number that divides into 45 exactly. These include 1 and 45, since 1 x 45 = 45,
3 and 15 since 3 x 15 = 45, and 5 and 9 since 5 x 9 = 45. Therefore the factors of 45 are 1, 3, 5, 9, 15 and 45. Notice that the only prime numbers in this list are 3 and 5. Therefore, the prime factors of 45 are 3 and 5.
For instance, 3 is a prime number that divides into 45. 5 is a prime number that divides 45. Those are the only prime numbers that divide into 45.
However, if you want all the factors of 45, you need to find every whole number that divides into 45 exactly. These include 1 and 45, since 1 x 45 = 45,
3 and 15 since 3 x 15 = 45, and 5 and 9 since 5 x 9 = 45. Therefore the factors of 45 are 1, 3, 5, 9, 15 and 45. Notice that the only prime numbers in this list are 3 and 5. Therefore, the prime factors of 45 are 3 and 5.
Galactus here are the answers that i got for my worksheet. Please post back and tell me if i got them right plz.Thanks
12-1,2,3,4,6,12
45-1,3,5,9,45
41-1,41
54-1,2,3,6,9,18,27,54
48-1,2,3,6,8,16,24,48
100-1,2,4,5,20,25,50,100
O the 100 one i sont know if all of them are right. I tried my best to get them.You helped me alot.Thanks.Sorry im posting back so late. Ive been outside. Well thanks for the help.Plz post back.
12-1,2,3,4,6,12
45-1,3,5,9,45
41-1,41
54-1,2,3,6,9,18,27,54
48-1,2,3,6,8,16,24,48
100-1,2,4,5,20,25,50,100
O the 100 one i sont know if all of them are right. I tried my best to get them.You helped me alot.Thanks.Sorry im posting back so late. Ive been outside. Well thanks for the help.Plz post back.
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If you are wanting private tutoring, you will need to contract with a service which offers such.Miclee said:
If you are wanting on-demand immediate replies (such as was indicated in your duplicate, and now deleted, thread), you will need to contract with such. (You will probably need to pre-pay.)
But, on free services such as this, with volunteers who surf by as they are able, you should expect to wait hours, if not days, for an online reply, and you should not expect to receive replies from only one other forum member.
I apologize for the confusion.
Eliz.
D
Deleted member 4993
Guest
Miclee said:
Here's a way to get ALL the factors. I'll use 90 as an example.
First, recognize that two of the factors are 1 and the number istself, in this case, 1 and 90.
Now, find all the prime factors.
2)90
3)45
3)15
----5
To the original list of 1 and 45, we add 2, 3 and 5. So far, the factors are 1,2,3,5 and 90.
2x3x3x5=90 from our division.
Now, multiply those three prime factors in every way possible.
2x3=6
2x5=10
3x3=9
3x5=15
2x3x3=18
2x3x5=30
3x3x5=45
This gives us the rest. The final list is 1,2,3,5,6,9,10,15,18,30,45 and 90.
First, recognize that two of the factors are 1 and the number istself, in this case, 1 and 90.
Now, find all the prime factors.
2)90
3)45
3)15
----5
To the original list of 1 and 45, we add 2, 3 and 5. So far, the factors are 1,2,3,5 and 90.
2x3x3x5=90 from our division.
Now, multiply those three prime factors in every way possible.
2x3=6
2x5=10
3x3=9
3x5=15
2x3x3=18
2x3x5=30
3x3x5=45
This gives us the rest. The final list is 1,2,3,5,6,9,10,15,18,30,45 and 90.