6 3/10÷0.28+1 8/100÷1.8-10.9 (1 3/4÷1/2-78 29/125÷25 2/5)÷3 1/2

6 3/10÷0.28+1 8/100÷1.8-10.9 (1 3/4÷1/2-78 29/125÷25 2/5)÷3 1/2= 6,3:0,28+1,08÷1,8-10,9(1,75:0,5-78,232: 25,4):3,5= 22,5+0,6- 10,9(3,5-3,08)= 23,1- 10,9*0,42= 23,1-4,578= 18,522