4-2.1/4 * (1.1/3-5/6) :10
=3 71/80 = 3,8875
!!!!!!!!!!!!!!!!!!!!!!
4-2.1/4 * (1.1/3-5/6) :10= 1)1 1/3-5/6=1/2 2)2 1/4•1/2=1 1/8 3)1 1/8:10=9/80 4)4-9/80=311/80=3 71/80