Question

Вычислить; 1)75-3,75; 2)0,48*25; 3)2/3-2; 4)4/7: 8 5)5 1/2*2/11 6)1 1/7: 1/14 7)-18: (-4,5);

Answer 1

$\tt \displaystyle 1)\; 75-3,\! 75=75,\! 00-3,\! 75=\boxed{71,\! 25} \\ \\ 2)\; 0,\! 48\cdot 25=\frac{48}{100} \cdot 25=\frac{48}4 =\boxed{12} \\ \\ 3)\; \frac23 -2=\frac23 -\frac63 =-\frac43 =\boxed{-1\frac13 } \\ \\ 4)\; \frac47 :8=\frac4{7\cdot 8} =\frac1{7\cdot 2} =\boxed{\frac1{14} } \\ \\ 5)\; 5\frac12 \cdot \frac2{11} =\frac{5\cdot 2+1}2 \cdot \frac2{11} =\frac{11\cdot 2}{2\cdot 11} =\boxed{1} \\ \\ 6)\; 1\frac17 :\frac1{14} =\frac87 \cdot \frac{14}1 =8\cdot 2=\boxed{16} \\ \\ 7)\; -18:(-4,\! 5)=18:\frac{45}{10} =18\cdot \frac29 =2\cdot 2=\boxed{4}$