до сотых a=2,435 b=1,923

a+b = 2,435 + 1,923 = 4,358

a-b = 2,435 - 1,923 = 0,512

a*b = 2,435 * 1,923 = 4,684,205

a:b = 2,435 / 1,923 ≈ 1,266