найти значение выражения (20 цел - 19 цел 3/4) - (17 цел 3/4 - 17 цел) + (2 цел 1/2 - 17/24) =

(20 цел - 19 цел 3/4) - (17 цел 3/4 - 17 цел) + (2 цел 1/2 - 17/24) = 1 7/24

1) 20-19 3/4=19 4/4-19 3/4=1/4

2) 17 3/4-17=17 3/4-16 4/4=3/4

3) 2 1/2-17/24=5/2-17/24=60/24-17/24=43/24=1 19/24

4) 1/4-3/4=-2/4=-1/2

5) - 1/2+43/24=-12/24+43/24=31/24=1 7/24