`1/2+3/4-5/6=6/12+9/12-10/12=5/12`
`(5/6+3/8)xx2/7=(20/24+9/24)xx2/7=29/24xx2/7=29/84`
`(7/6-3/4):3/5=(14/12-9/12)xx5/3=5/12xx5/3=25/36`
`6/7xx2/3:5/7=6/7xx2/3xx7/5=4/5`
` 1/2 + 3/4 - 5/6 = 6/12 + 9/12 - 10/12 = 5/12`
` ( 5/6 + 3/8) xx 2/7 = ( 20/24 + 9/24) xx 2/7 = 29/24 xx 2/7 = 29/84`
` ( 7/6 - 3/4) : 3/5 = ( 14/12 - 9/12) : 3/5 = 5/12 : 3/5 = 5/12 xx 5/3 = 25/36`
` 6/7 xx 2/3 : 5/7 = 6/7 xx 2/3 xx 7/5 = 4/5`
` 1/2 + 3/4 - 5/6 = 6/12 + 9/12 - 10/12 = 5/12`
` ( 5/6 + 3/8) xx 2/7 = ( 15/24 + 9/24) xx 2/7 = 29/24 xx 2/7 = 29/84`
` ( 7/6 - 3/4) : 3/5 = ( 14/12 - 9/12) : 3/5 = 5/12 : 3/5 = 5/12 xx 5/3 = 25/36`
` 6/7 xx 2/3 : 5/7 = 6/7 xx 2/3 xx 7/5 = 4/5`