Question

HELP :/ At the local pet store, Bloodfin Tetra cost $1.50 each and Angelfish cost $4.75 each. If Sarah bought 8 fish for a total cost of $21.75, not including tax, how many of each type of fish did she buy?

Answer 1

Sarah bough 3 Angelfish and 5 Bloodfin Tetra

Explanation:

Let a be the number of Angelfish fish and

b be the number of Bloodfin fish

Then according to the given statements

we get the following equations

`a+b = 8\ \ \ Eqn\ 1\\4.75a+1.50b=21.75\ \ \ Eqn\ 2`

From Equation 1

`a = 8-b`

Putting in equation 2

`4.75(8-b)+1.50b = 21.75\\38-4.75b+1.50b = 21.75\\38-3.25b = 21.75\\-3.25b = 21.75-38\\-3.25b = -16.25\\(-3.25b)/(-3.25) = (-16.25)/(-3.25)\\b = 5`

Putting b=5 in equation 1

`a+5 = 8\\a = 8-5 = 3`

Hence,

Sarah bough 3 Angelfish and 5 Bloodfin Tetra