Question

Efectuati: (-3/4) + (-4/21):(8/42

Answer 1

$( - \frac{3}{4}) + ( - \frac{4}{21}) : ( \frac{8}{42}) = - \frac{3}{4} - \frac{4}{21} : \frac{4}{21} = - \frac{3}{4} - \frac{4}{21} \times \frac{21}{4} = - \frac{3}{4} - \frac{4 \times 21}{21 \times 4} = - \frac{3}{4} - \frac{84}{84} = - \frac{3}{4} - 1 = - \frac{7}{4}$

Answer 2

( - 3 / 4 ) + ( - 4 / 21 ) : ( 8 / 42 ) = - 7 / 4

= ( - 3 / 4 ) - ( 4 / 21 ) × ( 42 / 8 ) =

= - 3 / 4 -  ( 4 / 8 ) × ( 42 / 21 ) =

= - 3 / 4 - ( 2 / 2 ) =

= - 3 / 4 - 4 / 4 =

= - 7 / 4