Algebra math HELP NOW! Fraction Busters

Now, come on Ariel,
You don't really expect us to do all your homework for you, do you?
Can you do any of these, or at least have a go.
The first one is a trick question.
The others do look pretty hard.
how old are you?

Can you do these for me ( also tell me what the common denominators are going to be)

a) 5/7 - 3/7
b) 5/6 - 1/12
c) 1/3 + 1/2
d) t/2 + 3t/2

I know it is really irritating being given more question when you have just asked for answers but I am trying to help you learn.
The sooner you get back to me, the sooner I can get back to you again. I'm a good teacher so you should take advantage.

a) 5/7 - 3/7
b) 5/6 - 1/12
c) 1/3 + 1/2
d) t/2 + 3t/2

A: 7 or 14(common denominator)
B:12
C:6
D:2 or 4

That's great Ariel, but I wanted you to actually work out tha answers as well.
Just use the smallest common denominator.
(I'm sorry I took so long to answer, I am often faster than that .)

Never mind, this is more important.
Looking at your questions.

For each one can you tell me what the smallest common denominator is. (For all the terms on both sides of the equal sign)
You obviously know how to get the number part, if there is a letter on the bottom you have to include that as well.

Now if you can do that, then I want you to multiply both sides by the smallest common denominator. It might be a good idea to introduce brackets to make sure you mulliply every term.
I'll do one for you
5:) 1687/90=-18/5k-2-5/3k (Please note that the ks are on the top eg. -18/5k=-18/5*k=-18k/5 )
131215 latex answer 2.JPG

Now make sure you understand it and then have a go at the others.
Get back to me and tell me how you are going.

Are these correct?:
1:) A=0.1
2:) P=1
3:) n=-0.256
4:)x=-0.657
5:) k=-3.548
6:) m=-3.642
7:)r=0.48
I think i did these right but can you check them?

Hi Ariel,
I am sorry but i don't think that they are correct.
Question 1 is a trick question. See if you can work out why. You don't need to do much working.
I'll finish question 5 for you, just in case it is only the end that you are having problems with.
I'll get back to you in a little while but in the mean time could you please choose one (not question 1 ) and show me your working.
Please leave your answer as a fraction because it is easier for me to check and because when you change it to a decimal you would often round it off and then it wouldn't be exact any more.
Basically I need you to tell or show me why you are having problems
I know you can't show me like i showed you, unless you scan in a hand written answer and attach it as an upload.
But show me your working, line by line, as best you can.
I'd really like to help you sort out these problems.

5:) 1687/90=-18/5k-2-5/3k