A hose fills a hot tub at a rate of gallons per minute. How many hours will it take to fill a ​-gallon hot​ tub?

Answer 1

You did not give the fill rate or the size of the hot tub though I can tell you how to do the problem in general or with numbers that I choose.

Let's say that the fill rate is 10 gallons per MINUTE. Let's say that the capacity of the hot tub is 120 gallons. Notice that the question asks how many HOURS will it take to fill the hot tub. The ACT and SAT are known for throwing tricks like this into the mix to keep you on your toes. Be careful of the units!

I recommend setting up a proportion, since these work for so many problems and can be solved with cross-multiplication.

10 gallons 120 gallons

--------------- = ------------------

1 minute x minutes

Cross-multiply and drop units to get: 10x = 120

Divide each side of the equation by 10 to find what x is, that is, how many MINUTES will will take to fill the hot tub.

10x 120

------- = ------

10 10

x = 12

However, the ACT doesn't want to know how many MINUTES it takes. They want to know how many HOURS it takes. However, you can be sure that the number of MINUTES it will be one of the options the ACT gives; do not choose this option. Instead, convert MINUTES to HOURS, again, using a proportion.

1 hour y hours

----------------- = ----------------

60 minutes x minutes

We will fill in 12 for x.

1 hour y hours

----------------- = ----------------

60 minutes 12 minutes

Now cross-multiply and drop units to get

60y = 12

Divide each side by 60 to get the value of 1y or the number of hours it takes to fill the hot tub.

60y = 12

----- ------

60 60

y = 1/5 or 0.2

Look for either 1/5 hour or 0.2 hour on the ACT choice of answers. Both are correct, but only one will be listed; choose it!!!

Of course, these are my numbers. You will need to fill in the values that they give you.

Answer 2

307/2.08/60 = your answer