Question

How many times smaller is 2 × 10-3 than 4 × 10-2? PLEASE HELP

Answer 1

The required "option A) 20" is correct.

Step-by-step explanation:

Let x be the smaller than 4 ×$10^{-2}$.

To find, the number of times smaller is 2 × $10^{-3}$ than 4 × $10^{-2}$ = ?

∴ x = $\dfrac{4\times 10^{-2}}{2\times 10^{-3}}$

= 2 × $10^{-2}$ × $10^{3}$

Using the identity,

$a^{m}=\dfrac{1}{a^{-m}}$

= 2 × $10^{-2+3}$

Using the identity,

$a^{m} \timesa^{n}=a^{m+n}$

= 2 × $10^{1}$

= 2 × 10

= 20

Thus, the required "option A) 20" is correct.