How to multiply and divide with scientific notation?

To multiply two scientific notation numbers, multiply their coefficients and add their exponents. To divide two scientific notation numbers, divide their coefficients and subtract their exponents

example multiply:  2 x 10^4  times 4 x 10^6 = 2x4 = 8 x 10 ^ 10

Example divide: 10 x ^8 divided by 5 x 10^4 = 10/5 = 2 x 10^4

answer set (b) 0.5, 3/4 80% is in order from least to greatest.  

step-by-step explanation:

in order to compare rational numbers to each other, it is much easier if they are in the same form.   typically, the best form in which to evaluate rational numbers is in decimals.   in order to convert a percent to a decimal, you would divide the given percentage by 100.   you can also accomplish the conversion by moving the decimal point over two places to the left.   for example, the decimal value of 80% is 80/100, or 0.8.   in order to convert a fraction to a decimal, you need to divide the numerator by the denominator.   for example, 3/4 is 0.75.   so, for choice (b) 0.5 3/4 (0.75), 80% (0.8) is the only choice in which the numbers are in order from least to greatest.