Question

Kevin and his children went into a restaurant and he bought $31.50 worth of hotdogs and drinks. Each hotdog costs $4.50 and each drink costs $2.25. He bought 3 times as many hotdogs as drinks.

Answer 1

He bought 6 hotdogs and 2 drinks

Explanation:

System of Equations

Kevin and his children went into a restaurant and bought $31.50 worth of hotdogs and drinks. Each hotdog costs $4.50 and each drink costs $2.25.

To solve the system of equations, we'll call the variables:

x = number of hotdogs

y = number of drinks

The first condition yields the equation:

4.50x + 2.25y = 31.50 [1]

It's also known he bought 3 times as many hotdogs as drinks, thus:

x = 3y [2}

Substituting [2] in [1]:

4.50(3y) + 2.25y = 31.50

Operating:

13.5y + 2.25y = 31.50

15.75y = 31.50

y = 31.50/15.75

y = 2

And

x = 3*2 = 6

He bought 6 hotdogs and 2 drinks