A piece of yarn is 18 meters long. From this piece, Ariana cuts four smaller pieces that are each 280 cm long. How much yarn, measured in meters, will she have left?*
18m = 1800 cm
1800/280 = 6.42
so, 6 pieces
or, think of it as a way to convert meters to pieces
18m * 100cm/m * 1piece/280cm = 6.42 piece