Given:
Henry can type 3500 words in 70 minutes.
Colin can type 1500 in 30 minutes.
Brian can type 2200 words in 40 minutes.
To find:
The person who types at the fastest rate of words per minute.
Solution:
We know that,
Using this formula, we get
Since 55>50, therefore Brian's types at the fastest rate of words per minute.