Question

Answer 1

a: \(\frac27+\frac57:\frac{2}{21}+\frac{19}{21}=\frac27+\frac57\cdot\frac{21}{2}+\frac{19}{21}\)

\(=\frac27+\frac{15}{2}+\frac{29}{21}=\frac{12+315+58}{42}=\frac{385}{42}\)

b: \(\frac35\cdot\left(\frac37\right)^5\cdot\left(\frac{21}{9}\right)^5+\left(\frac49\right)^6:\left(\frac{12}{27}\right)^6\)

\(=\frac35\cdot\left(\frac37\cdot\frac{21}{9}\right)^5+\left(\frac49:\frac{12}{27}\right)^6\)

\(=\frac35+1=\frac85\)