Answer :

luana
[tex]72\ words\ in\ one\ minute\\\\ x\ words\ in\ 5\ minutes\\\\Making\ proportion:\\ 72-1\\x-5\\\\cross\ multiplication\\\\ 72*5=x\\\\ x=360\\\\ In\ 5\ minutes\ Alex\ can\ type\ 360\ words.[/tex]
Divide 72 into 5 and you get 144 words in 5 minutes.