25/30 - 20/60 + 15/30= 5/6 - 1/3 + 1/2= 10/12 - 4/12 + 6/12= 12/12= 1
9/36 + 36/72 - 1/9= 1/4 + 1/2 - 1/9= 9/36 + 18/36 - 4/36= 23/36
9/21 - 16/42 + 1/7= 3/7 - 8/21 + 1/7= 9/21 - 8/21 + 3/21= 4/21
4/6 + 1/3 - 1/100= 2/3 + 1/3 - 1/100= 3/3 - 1/100= 1 - 0.01= 0.99
25/30 - 20/60 + 15/30
= 5/6 - 1/3 + 1/2
= 10/12 - 4/12 + 6/12
= 12/12
= 1
9/36 + 36/72 - 1/9
= 1/4 + 1/2 - 1/9
= 9/36 + 18/36 - 4/36
= 23/36
9/21 - 16/42 + 1/7
= 3/7 - 8/21 + 1/7
= 9/21 - 8/21 + 3/21
= 4/21
4/6 + 1/3 - 1/100
= 2/3 + 1/3 - 1/100
= 3/3 - 1/100
= 1 - 0.01
= 0.99