1) 1,25 + (-1 1/4) = 5/4 - 1 1/4 = 5/4 - 5/4 = 0.
2) 1 1/19 = 20/19 = 19/20 ( обратное число)
3) 19/20 + 0 = 19/20.
1) 1,25 + (-1 1/4) = 5/4 - 1 1/4 = 5/4 - 5/4 = 0.
2) 1 1/19 = 20/19 = 19/20 ( обратное число)
3) 19/20 + 0 = 19/20.