If Hank has 48 fish in his aquarium, and he has 11 times as many tetras as he has guppies, all we need to do to find out how many of each type he has is perform a system of trial-and-error equations until the problem is solved.
For the first try, let's say that Hank had 3 guppies. If Hank had 11 times as many tetras as he had guppies, then we just multiply 11 by 3.
11 3 = 33
Then, we just add the amount of tetras to the amount of guppies.
33 + 3 = 36
36 is less than 48, so Hank had more guppies than 3.
Let's try 5.
5 11 = 55
55 + 5 = 60
60 is greater than 48, which means that Hank has less than 5 guppies.
Now let's go between the two numbers that we already tried, to 4...
4 * 11 = 44
44 + 4 = 48
And here we have the answer!
If Hank had 48 fish, with 11 times as many tetras as he had guppies, then that means that Hank had 4 tetras and 44 guppies.
Hope that helped =)
