Question

It takes paul m minutes to mow the entire lawn.After he works k minutes,what part of the lawn is still unmowed?

Answer 1

The answer is . . . m - k minutes is the part of the lawn still unmowed.

You know it takes Paul m minutes to mow the entire lawn, and you know that he's mowed for k minutes so far . . .

 . . . the amount of time left is the total less the amount he's mowed so far

m - k  . . . is the time yet to be spent mowing the rest of the yard.

Answer 2

So work =time times rate or W=TR

so T=m-k
W=(m-k)R

if you want just m-k then m-k is the answer