Math 20 Math 25 Math Tips davidvs.net # Math 20 Pop Quiz #4

Time for another fun graded pop quiz!

Your final exam proves to the world that you have sufficient mastery of the math topics. We do not need to measure topic mastery with quizzes.

Your turn in homework tries to keep you from falling behind in class. These quizzes can also help with that.

Most importantly, this pop quiz checks if you can use our math tools to contribute meaningfully to an open-ended real-life issue.

## Sorting Word Problems

Now for something completely different!

Do not solve the world problems below. Merely sort them by which arithmetic operation is used to solve them: +, −, ×, or ÷. You can circle your choice below each word problem.

1. After a birthday party there is ½ of a cake left over. You eat ¼ of the leftover portion. What fraction of a whole cake do you eat? 2. After a birthday party there is ½ of a cake left over. You eat ¼ of a whole cake. How much of the leftover cake did you eat? 3. After a birthday party there is ½ of a cake left over. The entire cake cost \$16. What is the monetary value of the leftover portion? 4. After a birthday party there is ½ of a cake left over. You have six kids, so you cut the leftover portion into six pieces so they can each get a fair share. How much of a whole cake is each child's share? 5. After a birthday party there is ½ of a cake left over. You eat ¼ of the leftover portion. What percentage of the leftover portion do you eat? 6. After a birthday party there is ½ of a cake left over. You eat 20% of the leftover portion. What fraction of a whole cake do you eat? 7. Every morning you exercise on a treadmill for ½ hour. How much time is this per week? 8. Every morning you exercise on a treadmill for ½ hour. But this morning a phone call interrupted you. You only exercised for ⅓ of an hour. How much of your normal exercise time did you miss? 9. Every morning you exercise on a treadmill for ½ hour. Your weight and treadmill settings determine that you burn 700 calories per hour exercising. How many calories do you burn each morning? 10. Every morning you exercise on a treadmill for ½ hour. So do your three housemates. How much total time per day do the four of you spend using the treadmill?   12. Two-fifths of the students in a class are older than 20. Among those older students, ⅓ are earning an A. What fraction of the class consists of older A-level students? 13. Two-fifths of the students in a class are older than 20. Regardless of age, ⅓ of the students aced the first midterm. What fraction of the class consists of older students who aced the midterm? 14. Two-fifths of the students in a class are older than 20. One-quarter of the students in the class are younger than 18. What fraction of the class consists of students aged 18 to 20? 15. Two-fifths of the students in a class are older than 20. There are 40 students in the class. How many students are older than 20? 16. Two-fifths of the students in a class are older than 20. The older students are given a special assignment, and asked to work in four groups of equal size. (This works out. No group needs to have more or fewer students than any other group.) What fraction of the entire class is in each of these special assignment groups? 17. Two-fifths of the students in a class are older than 20. Regardless of age, 10 protractors are passed out randomly to the students. Estimate how many of the older students have protractors. 18. Two-fifths of the students in a class are older than 20. At a class party, they eat three-tenths of the consumed food. Do they eat more or less than their fair share? 