(5,69-2,85)•1,5+7,8•5,4-23,88

(5,69-2,85)*1,5+7,8*5,4-23,88=22,5 1)5,69-2,85=2,84 2)2,84*1,5=4,26 3)7,8*5,4=42,12 4)4,26+42,12=46,38 5)46,38-23,88=22,5