What I did was change both fractions into decimals:
.4 hrs = .8 pages
Then I multiplied them till they where in singular digits, like 1 instead of .2:
I got .4 x 5 and .8 x 5
Which gave me 2 and 4. I then divided them in half and got:
2 pages every 1 hour.
So your answer is: He types 2 pages/hour