Question

At the local pet store, zebra fish cost $1.80 each and neon tetras cost $2.10 each. If Ernesto bought 16 fish for a total cost of $30.90, not including tax, how many of each type of fish did he buy? Help ASAP!!

Answer 1

The number of each type of fish that Ernesto bought are 7 neon tetras and 9 zebra fishes.

• Let the zebra fish be Z.

• Let the neon tetras be N.

Given the following data:

• Total cost = $30.90

• Total number of fishes = 16 fishes.

To calculate the number of each type of fish that Ernesto bought:

How to solve a word problem.

First of all, we would assign a variable to each type of fish that Ernesto bought and then write a system of algebraic equations. Finally, we would solve the system of algebraic equations by using the substitution method.

Translating the word problem into an algebraic expression, we have;

$Z+N=16$    .....equation 1.

$1.80Z+2.10N=30.90$   .....equation 2.

From eqn. 1, we have:

$Z=16-N$      .....equation 3.

Substituting eqn. 3 into eqn. 2, we have:

$1.80(16-N)+2.10N=30.90\\\\28.80-1.80N+2.10N=30.90\\\\28.80+0.30N=30.90\\\\0.30N=30.90-28.80\\\\0.30N=2.10\\\\N=\frac{2.10}{0.30}$

N = 7 neon tetras.

For the zebra fish:

$Z=16-N\\\\Z=16-7$

Z = 9 zebra fishes.

Read more on word problems here: https://brainly.com/question/13170908