Question

Решить уравнения письменно, хелп (да, это опять я:>)

Answer 1

3) а)
$3.8(b - 1 frac{1}{6} ) = frac{19}{20} \ b - 1 frac{1}{6} = frac{19}{20} div 3.8 \ b - 1 frac{1}{6} = frac{19}{20} div frac{38}{10} \ b - 1 frac{1}{6} = frac{19}{20} times frac{10}{38} \ b - 1 frac{1}{6} = frac{1}{4} \ b = frac{1}{4} + 1 frac{1}{6} = frac{1}{4} + frac{7}{6} = frac{3}{12} + frac{14}{12} = frac{17}{12} = 1 frac{5}{12}$
б)
$1 frac{1}{4} (y - 1.2) = 5.5 \ y - 1. 2 = 5.5 div 1 frac{1}{4} \ y - 1. 2 = frac{55}{10} div frac{5}{4} \ y - 1.2 = frac{11}{2} times frac{4}{5} \ y - 1.2 = frac{22}{5} \ y - 1. 2 = 4.4 \ y = 4.4 + 1.2 = 5.6$
4)
а)
$(m - frac{3}{7} ) div 1 frac{1}{5} = 3.5 \ m - frac{3}{7} = 3.5 times 1 frac{1}{5} \ m - frac{3}{7} = frac{35}{10} times frac{6}{5} \ m - frac{3}{7} = frac{21}{5} \ m = frac{21}{5} + frac{3}{7} = frac{147}{35} + frac{15}{35} = frac{162}{35} = 4 frac{22}{35}$
б)
$(2.3 - m) div frac{3}{5} = 0.12 \ 2.3 - m = 0.12 times frac{3}{5} \ 2.3 - m = frac{12}{100} times frac{3}{5} \ 2.3 - m = frac{36}{500} \ 2.3 - m = 0.072 \ m = 2.3 - 0.072 = 2.228$