\[\boxed{\mathbf{Стр.\ 69.\ }еуроки - ответы\ на\ пятёрку}\]
\[\boxed{\mathbf{19.}}\]
\[300 + 300\ :6 = 300 + 50 =\]
\[= 350\ (кг) - овощей\ заготовил\ \]
\[фермер.\]
\[Ответ:350\ кг.\]
\[\boxed{\mathbf{20.}}\]
\[1)\ (60 \cdot 3)\ :(60\ :3) = 180\ :20 =\]
\[= 9\ раз.\]
\[2)\ (80 \cdot 2)\ :(80\ :2) = 160\ :40 =\]
\[= 4\ раза.\]
\[3)\ (100 \cdot 5)\ :(100\ :5) =\]
\[= 500\ :20 = 50\ :2 = 25\ раз.\]
\[\boxed{\mathbf{21.}}\]
\[Правило:\ \ a \cdot b.\]
\[a\backslash b\] | \[120\] | \[80\] | \[100\] | \[90\] |
---|---|---|---|---|
\[3\] | \[360\] | \[240\] | \[300\] | \[270\] |
\[5\] | \[600\] | \[400\] | \[500\] | \[450\] |
\[7\] | \[840\] | \[560\] | \[700\] | \[630\] |
\[2\] | \[240\] | \[160\] | \[200\] | \[180\] |
\[\boxed{\mathbf{22.}}\]
\[26 + 6 \cdot 8 = 26 + 48 = 74\]
\[80 - 7 \cdot 5 = 80 - 35 = 45\]
\[92 - 8 \cdot 3 = 92 - 24 = 68\]
\[700\ :100 \cdot 30 = 7 \cdot 30 = 210\]
\[810\ :90 \cdot 40 = 9 \cdot 40 = 360\]
\(420\ :60 \cdot 10 = 7 \cdot 10 = 700\)