1/4*4 3/4*16/57+(4 3/4+1 2/3)*16/21+2/27*4 1/2= 5/9
1)4 3/4+1 2/3=4 9/12+1 8/12=5 17/12=6 5/12=77/12
2) 1/4*4 3/4*16/57=1/4* 19/4*16/57=1/1*19/1*1/57=1/3
3)77/12*16/21=11/12*16/3=11/3*4/3=44/9
4)2/27*4 1/2=2/27*9/2=1/27*9/1=1/3
5)1/3+44/9+1/3=2/3+44/9=6/9+44/9=50/9=5 5/9