`A-(6/15+3/15)xx4/9=5/9`
`A-9/15xx4/9=5/9`
`A-4/15=5/9`
`A=5/9+4/15`
`A=37/45`
______________________________
`(B+7/8)xx36/14=15/4`
`B+7/8=15/4:36/14`
`B+7/8=35/24`
`B=35/24-7/8`
`B=7/12`
`A- (6/15+3/15)xx4/9=5/9`
`A- 9/15 xx 4/9 = 5/9`
`A- 9/15 = 5/9 : 4/9`
`A- 9/15 = 5/9 xx 9/4`
`A- 9/15 = 5/4`
`A= 5/4 + 9/15`
`A= 37/20`
`----------`
`(B+7/8)xx36/14=15/4`
`B+7/8= 15/4 : 36/14`
`B+7/8= 15/4 xx 14/36`
`B+7/8=35/24`
`B= 35/24 - 7/8`
`B=7/12`
ta có :
`7/12 và 37/20`
`MSC:60`
`7/12=(7xx5)/60= 35/60`
`37/20=(37xx3)/60= 111/60`
vậy `A<B`
Bổ sung so sánh `A` và `B`
`MSC:180`
`A=37/45=148/180`
`B=7/12=105/180`
Vì `148 > 105=>148/180 > 105/180`
Hay `A > B`
A−(615+315)×49=59A-(615+315)×49=59
A−915×49=59A-915×49=59
A−415=59A-415=59
A=59+415A=59+415
A=3745A=3745
______________________________
(B+78)×3614=154(B+78)×3614=154
B+78=154:3614B+78=154:3614
B+78=3524B+78=3524
B=3524−78B=3524-78
B=712
