Answer:
16 problems a minute
Step-by-step explanation:
Unit rate = "the 1 value"
The "1", in this case, would be 1 minute.
So, we need to find the number of questions she is solving every minute.
To do this, either divide 40 by 2.5 (2 and 1/2), or 80 by 5 Dividing either will give you the number 16, and this is your answer.
