Question

Mark the correct alternative in each of the following:

$9\times \left(-\frac{1}{3}\right)\times \left(-3\right)\times \left(-\frac{1}{9}\right)=$

(a) 1 (b) −1 (c) −3 (d) 3

Answer 1

Since the number of negative terms in the product is odd. Therefore, their product is negative.

$$\begin{gathered} 9\times \left(-\frac{1}{3}\right)\times \left(-3\right)\times \left(-\frac{1}{9}\right) \\ =9\times \left(-\frac{1}{9}\right)\times \left(-\frac{1}{3}\right)\times \left(-3\right) \\ =-\left(9\times \frac{1}{9}\times \frac{1}{3}\times 3\right) \\ =-\left(1\times 1\right) \\ =-1 \end{gathered}$$

Hence, the correct answer is option (b).