percentage: 90% with 47 class periods

Question

If I have to be present for 90% of my class and there are 47 class periods how many absences can I have

Answer 1

Hi Esmeralda!

To find out what 90% of 47 class periods is, you first must change the percent to a decimal. To do this, always move the decimal place two places to the left. In this case 90% becomes 0.90.

Now you must multiply 0.90 by 47 which gives you 42.3. Since 42.3 class periods does not make a lot of sense, we must round the answer to a whole number. You must be present for 90% of the class periods, so we cannot round down. Therefore, you must be present for 43 class periods. To answer the question of how many absences you can have, subtract 43 from 47 to get 4 absences.