To complete a train track, 66 wood ties are needed at one end, and 129 wood ties are needed at the other end. the track builders want to have a few extra ties in case any split or have knots in them. they put in an order for enough ties to finish the train track.

which statement is correct?

a.
the builders should order the exact number of ties they need which is 66 and 129.

b.
the builders should estimate that they need 70 + 130 ties and order 200 ties.

c.
the builders should estimate that they need 60 + 130 ties and order 190 ties.