This is a set of 16 task cards designed to help students evaluate whether to multiply or divide with a fraction in a problem solving situation. These are all situations in which whole numbers are either multiplied or divided by a fraction. All of these cards use only unit-fractions (all numerators of 1), which means that the answers are very different when you multiply or divide. That should make it more obvious to the students which operation would make sense in a given situation, and it keeps the fraction computation more basic.
These were created to be used with students who are only learning about multiplying and dividing with unit fractions. That is how the Core Math standard is being implemented at this point in my district for fifth graders. I have another set of task cards available on TPT that involve more advanced dividing/multiplying by a fraction.
This is an 8-page PDF file that includes 4 pages of task cards (4 per page), a 2-page answer key, and a 2-page recording sheet.