2/6*5/6+3/2:9/10-3/2*13/18

1) 2/6 * 5/6 = 10/64 = 5/32 
2) 3/2 : 9/10 = 5/3 = 1 2/3
3) 3/2 * 13/18 = 13/12 = 1 1/12
4) 5/32 + 1 2/3 - 1 1/12 = 15/96 + 1 64/96 - 1 8/96 = 1 79/96 - 1 8/96 = 71/96