Question

[tex [\frac{1}{3} ] [/tex]·$(10-\frac{1}{4} )-3\frac{2}{5} ]:(2-\frac{4}{5} )=$

AJUTOR VA ROG!!!!

Answer 1

→ introduc intregii in fractie

3 intregi si 2 / 5 = ( 3 x 5 + 2 ) / 5 = 17 / 5

[ 1 / 3 × ( 10 - 1 / 4 ) - 17 / 5 ] : ( 2 - 4 / 5 ) =

= [ 1 / 3 × ( 40 / 4 - 1 / 4 ) - 17 / 5 ] : ( 10 / 5 - 4 / 5 ) =

= ( 1 / 3 × 39 / 4 - 17 / 5 ) : 6 / 5 =

= ( 13 / 4 - 17 / 5 ) × 5 / 6 =

= ( 65 / 20 - 68 / 20 ) × 5 / 6 =

= ( - 3 / 20 ) × 5 / 6 =

= ( - 3 / 6 ) × ( 5 / 20 ) =

= ( - 1 / 2 ) × ( 1 / 4 ) =

= - 1 / 8

Answer 2

$[\frac{1}{3} \times (10 - \frac{1}{4}) - 3 \frac{2}{5}] : (2 - \frac{4}{5}) = \\ \\ 10 - \frac{1}{4} = \frac{10}{1} - \frac{1}{4} = \frac{10 \times 4}{1 \times 4} - \frac{1}{4} = \frac{40}{4} - \frac{1}{4} = \frac{40 - 1}{4} = \frac{39}{4} \\ \\ \frac{1}{3} \times \frac{39}{4} = \frac{1 \times 39}{3 \times 4} = \frac{39}{12} = \frac{13}{4} \\ \\ 3 \frac{2}{5} = \frac{3 \times 5 + 2}{5} = \frac{17}{5} \\ \\ \frac{13}{4} - \frac{17}{5} = \frac{13 \times 5}{4 \times 5} = \frac{17 \times 4}{5 \times 4} = \frac{65}{20} - \frac{68}{20} = \frac{65 - 68}{20} = - \frac{3}{20} \\ \\ 2 - \frac{4}{5} = \frac{2}{1} - \frac{4}{5} = \frac{2 \times 5}{1 \times 5} = \frac{10}{5} - \frac{4}{5} = \frac{10 - 4}{5} = \frac{6}{5} \\ \\ - \frac{3}{20} : \frac{6}{5} = \frac{ - 3}{20} \times \frac{5}{6} = \frac{ - 3 \times 5}{20 \times 6} = - \frac{15}{120} = - \frac{1}{8}$