2019 AMC 8
Complete problem set with solutions and individual problem pages
Problem 9 Easy
Alex and Felicia each have cats as pets. Alex buys cat food in cylindrical cans that are cm in diameter and cm high. Felicia buys cat food in cylindrical cans that are cm in diameter and cm high. What is the ratio of the volume of one of Alex's cans to the volume of one of Felicia's cans?
- A.
- B.
- C.
- D.
- E.
Answer:B
Solution 1
Using the formula for the volume of a cylinder, we get Alex, , and Felicia, . We can quickly notice that cancels out on both sides and that Alex's volume is of Felicia's leaving as the answer.
 
Solution 2
Using the formula for the volume of a cylinder, we get that the volume of Alex's can is , and that the volume of Felicia's can is . Now, we divide the volume of Alex's can by the volume of Felicia's can, so we get , which is .
