Using Standard Form

Question 1:

3.3 \times 10^{6} + 3.5 \times 10^{8}

3.533 \times 10^{8}

Question 2:

7.3 \times 10^{6} - 1.1 \times 10^{5}

7.19 \times 10^{6}

Question 3:

2 \times 10^{-4} \times 3 \times 10^{5}

6 \times 10^{1}

Question 4:

\frac{6.6 \times 10^{4}}{8.4 \times 10^{-5}}

7.86 \times 10^{8}