Answer:
Sarah bough 3 Angelfish and 5 Bloodfin Tetra
Step-by-step 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
[tex]a+b = 8\ \ \ Eqn\ 1\\4.75a+1.50b=21.75\ \ \ Eqn\ 2[/tex]
From Equation 1
[tex]a = 8-b[/tex]
Putting in equation 2
[tex]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\\\frac{-3.25b}{-3.25} = \frac{-16.25}{-3.25}\\b = 5[/tex]
Putting b=5 in equation 1
[tex]a+5 = 8\\a = 8-5 = 3[/tex]
Hence,
Sarah bough 3 Angelfish and 5 Bloodfin Tetra