Преобразуйте десятичные дроби в обыкновенные и вычислите: 1) 0,5 + 1/3; 3) 0,125 + 5/12; 2) 2/3 - 0,25; 4) 3,25 - 2 9/14.

0,5+ 1/3= 5/10 + 1/3= (15+10)/30 = 25/30 = 5/62/3-0,25= 2/3-25/100= 2/3 - 1/4 = (8-3)\\12 = 5/120,125+5/12 = 125/1000+ 5/12 = 1/8 + 5/12 = (3+10)/24 = 13/243,25-2 9/14 = 3 1/4 - 2 9/14 = 13/4 - 37/14 = (91-74)/28 = 17/28

1) 5/10 + 1/3 = 1/2 + 1/3 = (1*3+1*2)/6 = 5/6; 2) 2/3 - 25/100 = 2/3 - 1/4 = (2*4-1*3)/12 = (8-3)/12 = 5/12; 3) 125/1000 + 5/12 = 1/8+5/12=(1*3+5*2)/24 = (3+10)/24 = 13/24;4) 3 25/100 - 2 9/14 = 1 1/4-9/14 = 1 14/56 - 36/56 = (70-36)/56=34/56=17/28.