Question

13. Вычислите.СРОЧНОООО ДАЮ 15 БАЛЛОООООВ ​

Answer 1

$4 \div (5 \frac{1}{3} + 2 \frac{2}{3} ) = 4 \div7 \frac{3}{3} = 4 \div 8 = 0.5$

$( - \frac{1}{12} + 6 \frac{1}{4} ) \times 3 = ( - \frac{1}{12} + 6 \frac{3}{12} ) \times 3 = \\ 6 \frac{2}{12} \times 3 = 6 \frac{1}{6} \times 3 = \frac{37 \times 3}{6} = \frac{37}{2} = 18 \frac{1}{2} = 18.5$

$6 \times (7 \frac{4}{9} -8 \frac{5}{18} ) = 6 \times (7 \frac{8}{18} - 8 \frac{5}{18} ) = \\ 6 \times (7 \frac{8}{18} - 7 \frac{23}{18} ) = 6 \times \frac{15}{18} = 5$

$- \frac{1}{4} \times ( - 1 \frac{1}{15} ) \div ( - 4) = \\ - \frac{16}{4 \times 15 \times 4} = - \frac{1}{15}$