Answer:
9/12, 2/6, 1/2
Step-by-step explanation:
First start with the original fractions given and figure out how 4 got to 12
3/4=x/12 so divide 12/4 = 3 so they multiplied 4 by 3 to get to 12 so just do that to the top as well.
3 x 3 = 9
3/4 = 9/12
For the second one you do the same thing
2/1 = 2
3 x 2 = 6
1/3 = 2/6
For this last one just choose any number you want to multiply since its open ended.
2/4
Im just going to simplify it. Which means you do the reverse of the other two instead of multiplying youd divide the 2 numbers by a common factor which would be 2 in this case.
2/4 = 1/2
