Let’s Solve for m
p=3rmv^2
Step 1 Flip the equation
3mrv^2=p
Step 2 Divde Both Sides by 3rv^2
3mrv^2/3rv^2=p/3rv^2
m=p/3rv^2
ANSWER
m=p/3rv^2
First you add the 1/4 and 3/4 together forgetting the /4 and adding the 1+3, that makes 4/4 which is a 1 then add that 1 to the 1 and 2 left over to get the answer