Carla needs to complete her science homework. She has 20 pages to read unfortunate questions to answer. If it takes Carla 10 minutes to read four pages, how many minutes will it take her to read the full assignment?
Carla reads 4 pages every 10 minutes, so she reads 1 page in 10/4 = <<10/4=2.5>>2.5 minutes.
Thus, it will take her 20 * 2.5 = <<20*2.5=50>>50 minutes to read the full assignment. Answer: \boxed{50}.