2 5/8 : 1 3/4= 0,9 : 1/5= 3 1/7 : 2/7 - 1 : 2 1/3
1)2 5/8 : 1 3/4=21/8*4/7=3/2=1 1/2;/// 2)0,9 : 1/5=9/10*5/1=9/2=4 1/2; /// 3)3 1/7 : 2/7 - 1 : 2 1/3=22/7*7/2-1/1*3/7= 11/1-3/7=77/7-3/7=74/7=10 4/7
2 5/8 : 1 3/4 = 21/8 * 4/7 = 3/2 = 1 1/2 0,9 : 1/5 = 9/10 * 5/1 = 9/2 = 4 1/2 3 1/7 : 2/7 - 1 : 2 1/3 = 22/7 * 7/2 - 1 * 3/7 = 11 - 3/7 = (77-3)/7 = 74/7 = 10 4/7