1) (2/47)*9.4 + 5.6 = 0.4 + 5.6 = 6

2) 2.1 - (6.2*3)/31 = 2.1 - 18.6/31 = 2.1 - 0.6 = 1.5

3) 5.8:(9 2/3) + 8.04 = 5.8:(29/3) + 8.04 = 5.8*(3/29) + 8.04 = 0.6 + 8.04 = 8.64