Use fraction strip or tools to find the sum. write your answer in simplest form. 3/4+1/3

9/12+4/12 the answer would be 

1 and 1/12

I am not sure what you mean by "tools" but here's a very efficient method (in my opinion) to solving fractions. 

1) Find the LCD (least common denominator)
The LCD of the two fractions given above is 12 

2) Find fractions that are equivalent to the given fractions and as the LCD as the denominator of the equivalent fraction (hmm.. sounds complicated but it really isn't.) 

To get to 12 from 4 you need to multiply 4 by 3. So whatever you do to the denominator you do to the numerator. So 3 x 3 = 9. The equivalent fraction is 9/12. 

To get from 12 from 3 you need to multiply 3 by 4. So whatever you do to the denominator you do to the numerator. So 1 x 3 = 3. The equivalent fraction is 3/12. 

3) Add the numerators
Since you have the denominators of the two fractions now be the same, you are now just to add the numerators of the two (new) equivalent fractions. 

9/12 + 3/12 = 12/12 = 1