You need to add up the total number of CDs sold, and that is your denominator. The numerator would be the number sold in April, so 110. From there, simplify.
The answer would be which is . The steps are find the total sold, then put the amount sold in april over the total sold. You can maybe simplify it with a calculator.
Scientific notation is used in science because the number can be vary from so much that using decimal is making it hard. The number expressed in form. Both number in the question is already in scientific notation. Then to multiply the number and keep it at scienfitic notation the calculation should be: