Answer:
Explanation:
First we gotta make sense of what they are saying. Also, the names are way too similar.
If someone has 1/3 as much of something as another, say say person A had 1 thing and person B had 3, that means B's stuff is 3 times A's. or B=3*A. Flipped for the other way Person B has 4 times what person C does then 4B=C. of course you could use algebra to write both the other way, B/3=A and B=C/4. Hopefully that makes sense. If not I recommend trying to plug in real numbers and see how it works out.
Anyway in this case Arlene in this case has 1/3 as many as Isabelle. So
3*Arlene = Isabelle.
Also Isabelle has 5 times as many as Anaele so
Isabelle/5 = Anaele
Then, it says Anaele has 18 goldfish, so now we can start plugging in.
Isabelle/5=18 Multiply both sides by 5
Isabelle = 90
You can think of it logically too, if isabelle has five times as many as Anaele and Anaele has 18, you should multiply it by 5.
Plugging it into the first equation then gets
3*Arlene = 90
Arlene = 30 because 30 is 1/3 of 90.
Hopefully this helped though. You could have also set both equations just equal to Isabelle and solved it in one step.
3*Arlene = Isabelle = 5*Anaele
3*Arlene = 5*Anaele
3*Arlene = 5*18
Arlene = (5*18)/3 = 30