lisa cut a log into 4 pieces in 6 minutes. she then cut a smaller log into 8 pieces. how long should the job have taken if she worked at the same rate she had worked when cutting the first log? show all work and prove your answer.

To cut a log into 4 pieces takes 3 cuts, so each cut took 2 minutes.

So to cut a log into 8 pieces requires 7 cuts.
Ignoring the fact that the smaller log should take less time for a cut,
to make the 7 cuts would then take 14 minutes.

So the total time for the 10 cuts is 20 minutes.