Dye for our new line of blue jeans is being blended in a mixing tank. The desired color of blue is produced using a concentration of 1500 ppm blue dye, with a minimum acceptable concentration of 1450 ppm. At 9 A.M. today the dye injector plugged, and the dye flow was interrupted for 10 min, until we realized the problem and unclogged the nozzle. For how many minutes was the flow leaving the mixer off-specification (< 1450 ppm)?

Water 20gal/min