Nika baked three loaves of zucchini bread. Each cake needed StartFraction 17 over 4 EndFraction cups of flour. Which expression shows the best estimate of the number of cups of flour that Nika used? 4 + 4 + 4 = 12 5 + 5 + 5 = 15 4 + 4 + 4 = 16 17 + 17 + 17 = 51