Question

Inma’s pet store sells fantail goldfish and comet goldfish. Each aquarium of fantail goldfish has 9 fish

and each aquarium of comet goldfish has 13 fish. There are a total of 145 of these two types of

goldfish in the store, with 6 aquariums of fantail goldfish. How many aquariums of comet goldfish

are there?

햠 3

햡 5

햢 6

햣 7

Answer 1

Let's denote the number of aquariums of comet goldfish as \( c \).

From the problem, we know the following:

- Each aquarium of fantail goldfish has 9 fish, and there are 6 aquariums of fantail goldfish. Therefore, the total number of fantail goldfish is:
\[
6 \text{ aquariums} \times 9 \text{ fish per aquarium} = 54 \text{ fantail goldfish}
\]

- Each aquarium of comet goldfish has 13 fish. Thus, the total number of comet goldfish is:
\[
13c
\]

We know that the total number of goldfish (fantail and comet) is 145. Therefore, we can write the equation:
\[
54 + 13c = 145
\]

Now, we will solve for \( c \):
\[
13c = 145 - 54
\]
\[
13c = 91
\]
\[
c = \frac{91}{13}
\]
\[
c = 7
\]

Thus, the number of aquariums of comet goldfish is \( \boxed{7} \).