1)2 1/6* 6=13/6*6=13
(5/12+1 1/3)*3=(5/12+4/3)*3=((5+16)/12)*3=(21/12)*3=7/12
2)(2/5*x-2 2/3)/15=2
2/5*x-8/3=30
2/5*x=30+8/3
2/5*x=98/3
x=(98/3)/(2/5)=(98*5)/(3*2)=490/6=245/3=81 2/3
3)a) 5/6*b+3/10*b-7/15*b=50/60*b+18/60*b-28/60*b=40/60*b=4/6*b=2/3*b
б)3 5/6*y-2 5/12*y+ 1 1/3*y=46/12*y-29/12*y+16/12*y=33/12*y=2 9/12*y=2 3/4*y
4) 4 4/9*5/8+5/8*3 5/9= 5/8*(40/9+32/9)=5/8*72/9=5/8*8=5