Question

PLEASE HELP ILL GUVE EXTRA POINTS PLEASE!!!

Answer 1

Answer:

$\boxed{\bf 7 \times 10 {}^{ - 3}}$

Step-by-step explanation:

• $\cfrac{6.3}{9} \times \dfrac {10 ^{ - 5} }{10 {}^{ - 3} }$
• $0.7 \times \cfrac{10 {}^{ - 5} }{10 {}^{ - 3} }$
• $0.7 \times 10 { }^{ - 5 - 3 \times - 1}$
• $0.7 \times 10 {}^{ - 5 + 3}$
• $0.7 \times 10 { }^{ - 2}$

Write 0.7 *10^-2 into scientific notation:

• $7 \times 10 {}^{ - 3}$

Hope this helps! ^^"

Answer 2

Answer:

$7 \times 10^{-3}$

Step-by-step explanation:

$\begin{aligned}\dfrac{6.3 \times 10^{-5}}{9 \times 10^{-3}} & =\dfrac{6.3}{9} \times \dfrac{10^{-5}}{10^{-3}}\\\\& = 0.7 \times \dfrac{10^{-5}}{10^{-3}}\end{aligned}$

$\textsf{Apply exponent rule} \quad \dfrac{a^b}{a^c}=a^{b-c}:$

$\begin{aligned}\implies 0.7 \times \dfrac{10^{-5}}{10^{-3}} &=0.7 \times 10^{-5-(-3)}\\& = 0.7 \times 10^{-2}\end{aligned}$

$\textsf{Rewrite}\:0.7\:\textsf{as}\: 7 \times 10^{-1}:$

$\implies 0.7 \times 10^{-2}=7 \times 10^{-1} \times 10^{-2}$

$\textsf{Apply exponent rule} \quad a^b \times a^c=a^{bc}:$

$\implies 7 \times 10^{-1} \times 10^{-2}=7 \times 10^{-3}$