Question

a) 15 ×(0,5 - ⅙+0,6)
b) [0,5 + 0,(3)]: [1,1(6)-⅙
c)
$\sqrt{27} + \sqrt{12} - \sqrt{75}$

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Answer 1

$a) 15*(0,5-\frac{1}{6}+0,6)= 15*(\frac{5}{10} -\frac{1}{6} +\frac{6}{10} )=15*(\frac{30}{60} -\frac{10}{60} +\frac{36}{60} )\\\\15*(\frac{30-10+36}{60} )=15*\frac{56}{60} =\frac{56}{4} =14$

$b)\ [0,5+0,(3)] : [1,1(6)-\frac{1}{6}]=(\frac{5}{10} +\frac{3}{9}):(\frac{116-11}{90} -\frac{1}{6} )\\\\(\frac{45}{90} +\frac{30}{90}):(\frac{105}{90} -\frac{15}{90})=\frac{75}{90} :\frac{90}{90}=\frac{75}{90}=\frac{5}{6}$

$c)\ \sqrt{27}=3\sqrt{3}\\\\\sqrt{12}=2\sqrt{3}\\\\\sqrt{75}=5\sqrt{3}\\\\\sqrt{27}+\sqrt{12}-\sqrt{75}=3\sqrt{3}+2\sqrt{3}-5\sqrt{3}=0$