5乘四分之九减0.4除0.9等于多少 要有算式 九分之七乘十五分十四加九分之七除15等于多少 要有算式

5*9/4-0.4*0.9
=45/4-0.36
=11.25-0.36
=10.89
7/9*14/15+7/9÷15
=98/135+7/9*1/15
=98/135+7/135
=105/135
=7/9
(2/12+3/47)*12-36/47
=2*12/12+3*12/47-36/47
=2
1.8-(4/14+7/24)*3
=1.8-(12/14+21/24)
=1.8-(6/7+7/8)
=1.8+(48/56+42/56)
=9/5+90/56
=9/5+45/28
=252/140+45/140=297/140

5×9/4-0.4÷0.9
=5×9/4-4/9
=45/4-4/9
=405/36-16/36
=389/36
≈10.8
7/9×14/15+7/9÷15
=98/135+7/135
=105/135
=21/27
≈0.78
（2/12+3/47）×12-36/47
=2/12×12+3/47×1...