The question is incomplete. The complete question is below.
At Fun Burger, the burger master can make burgers at the rate of 4 burgers/minute. In order to address the heavy volume of costumers he needs to continue his rate for 30 minutes. If he continues to make burgers at this pace, how many hamburgers will the Burger Master make in 30 minutes?
Answer: 120 burgers
Explanation: Rate is a ratio of things done related to time.
The Burger Master can produce 4 burger each minute, so
1 minute = 4 burgers
Then after 30 minutes:
1 minute = 4 burgers
30 minutes = x
x = 30*4
x = 120
Therefore, after 30 minutes, the person produced 120 burgers.