Вычислите удобным способом 1/4+(-1'1/4)+4'3/8+(-6'1/4)
1/4+(-1'1/4)+4'3/8+(-6'1/4) = (-1'1/4 -6'1/4)+ (4'3/8+1/4)= -7'2/4 + 4'5/8 = -3'1/8