Question

(3.2 * 10000000) -3

Answer 1

The exponents distribute over factors:

$(ab)^c = a^c \times b^c$

so, you have

$(3.2 \times 10^6)^{-3} = 3.2^{-3} \times (10^6)^{-3}$

Let's focus on each factor: applying the definition of negative exponents, you have

$3.2^{-3} = \cfrac{1}{3.2^3} \approx 0.03$

While for the power of 10, you can use the following rule

$(a^b)^c = a^{bc}$ to write

$(10^6)^{-3} = 10^{6\cdot (-3)} = 10^{-18}$

So, the expression evaluates to

$0.03\times 10^{-18} = 3\times 10^{-20}$