Respuesta :

I expect the answer to be 4 because 60 divided by 4 equals 15 so  3/4 is 45 min. So I multiplied 45 to a few numbers to see which number gets to 3 hours and it was 4. 
THE ANSWER IS 4

1 hour is equivalent to 60 minutes

3/4 hours is - 60 minutes x 3/4 = 45 minutes

3 hours are equivalent to 60 minutes/hr x 3 hr = 180 minutes

it takes Cindy 45 minutes to complete a puzzle

so it takes her 45 minutes for - 1 puzzle

then in 180 minutes she can make - 1/45 x 180 = 4 puzzles

in 3 hours she can complete 4 puzzles