Elle went to Pet Smart and bought 4 goldfish and 3 turtles for $28. Later that day, Warren went to Pet Smart and bought 6 goldfish and 1 turtle for $10. How much does 1 goldfish cost?

1 Answer
Nallasivam V
Oct 7, 2015

Price of gold fish $1/7

Explanation:

Let g be the price of goldfish
Let t bt the price of turtles
Then -
4g+3t=28 ----------------(1)
6g+1t=10------------------(2)

Solve the 1st equation for t
t=10-6g
4g+3(10-6g)=28
4g+30-18g=28
-14g=28-30=-2
g=(-2)/(-14)=1/7
Price of gold fish $1/7

This is optional. This is not asked in the prolem
Substitute the value g=1/7 in equation (2)

4(1/7)+3t=28
4+21t=196
21t=196-4=192
t=192/21

Price of one turtle $ 192/21

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