2 1/3+4 1/10:(2 7/15-5/12)×5/6
2 1/3 + 4 1/10 : ( 2 7/15 - 5/12 ) * 5/6 = 2 1/3+4 1/10:(148/60-25/60)*5/6 = 2 1/3+4 1/10 : 2 1/20*5/6 = 2 1/3 + 81/20:41/20*5/6 = 2 1/3+2*5/6 = 7/3+10/6 = 24/6 = 4