Question

The value of x${}^{1/2}$ .y${}^{-1}$ . z${}^{2/3}$, when x = 9 , y = 3 and z = 8 is

• A. 18
• B. 12
• C. 6
• D. 8
• E. 4

Answer 1

The correct option is E

4

$\begin{array}{c}{x}^{1/2}{y}^{-1}.z^{2/3}={\left(9\right)}^{1/2}.{\left(3\right)}^{-1}.{\left(8\right)}^{2/3}\\ ={\left(3^2\right)}^{1/2}.{\left(3\right)}^{-1}.{\left(2^3\right)}^{2/3}=3.\frac{1}{3}.2^{\left(3\times \frac{2}{3}\right)}\\ =2^2=4.\end{array}$