Question

Express the answer in scientific notation:

5.0 x 10^-7mg + 4 x 10^-8mg

Answer 1

4 * 10^-8 mg = .4 * 10^-7 mg divide and multiply by 10

5.0 x 10^-7mg + .4 x 10^-7 mg = 5.4 x 10^-7 mg

Also 5.4 x 10^-7 mg = 5.4E-7 mg