1.) first, subtract (3.14 - 1.674 = 1.466) then, subtract 9 to 1.466 and you'll get == 7.534
2.) Add 14.28 + 11.219 = 25.499 and subtract, 14.28 - 11.219 = 3.061 , add the sum and the difference (25.499 + 3.061 = 28.56)
==28.56
3.) subtract 604 - 406.064 = 197.936 and add 604 + 406.064 = 1010.064 , subtract the sum and the difference ( 1010.064 - 197.936 = 812.128)
== 812.128