You can find which is fastest by setting each up as a fraction;
[tex] \frac{220}{8} = 27.5 \frac{words}{minute} \\
\frac{600}{12} = 50 \frac{w}{m} \\
\frac{350}{10} = 35 \frac{w}{m} \\
\frac{225}{5} = 45 \frac{w}{m} [tex]
Since 50 is the highest amount of words per minute, '600 words in 12 minutes' is your answer.
