(56+8/11)/9
=6+2/9+8/99
=6又33分之10
（2又2/9×4/5+2又2/9x6.2-5.8x2又2/9-1/5÷9/20）x9/20 2又2/9 =20/9
=（2又2/9×4/5+2又2/9x6.2-5.8x2又2/9-1/5×20/9）x9/20
=20/9（4/5+6.2-5.8-1/5）x9/20
=(0.8-0.2+6.2-5.8)
=1