Question

4 1/2×5 2/3-5 1/4; 11 1/3÷4/21+8 1/2;

Answer 1

Ответ:

1) 4 1/2×5 2/3-5 1/4 =

$4\frac{1}{2}*5\frac{2}{3}-5\frac{1}{4} =\frac{9}{2} *\frac{17}{3} -\frac{21}{4}=\frac{3}{2}*\frac{17}{1}-\frac{21}{4}=\frac{51}{2}-\frac{21}{4}=\frac{102-21}{4} =\frac{81}{4} =20\frac{1}{4}=20,25$

2) 11 1/3÷4/21+8 1/2 =

$11\frac{1}{3}:\frac{4}{21}+8\frac{1}{2}= \frac{34}{3}*\frac{21}{4} + \frac{17}{2} = \frac{34}{1} *\frac{7}{4} + \frac{17}{2} = 17 *\frac{7}{2}+ \frac{17}{2}=\frac{119}{2} + \frac{17}{2}= \frac{119+17}{2} \\\\= \frac{136}{2}=68$