Ответ:(72 + a) + 18 = a + (72 + 18) = a + 90.456 + (b + 144) = b + (456 + 144) = b + 600.625 + c + 165 = c + (625 + 165) = c + 790.d + 2 157 + 2 943 = d + (2 157 + 2 943) = d + 5 100.