(- 2 2/3 - 2 4/21 ) : 17/21 + 5,1 = -0,9
выражением:
= (- 2 14/21 - 2 4/21 ) * 21/17 + 5,1 =
= - 4 18/21 * 21/17 + 5,1 =
= - (102*21)/(21*17) +5,1=
= -6 + 5,1 =
= - (6,0 - 5,1) =
= - 0,9
по действиям:
1) - 2 2/3 - 2 4/21 = - 2 14/21 - 2 4/21 =
= -(2 14/21 + 2 4/21) = - 4 18/21 = - 4 6/7
2) - 4 6/7 : 17/21 = - 34/7 * 21/17 = - (2*3)/(1*1) = - 6
3) -6 + 5,1 = - (6,0 - 5,1) = -0,9