jillian is selling boxes of cookies to raise money for her basketball team. the 10 oz. box costs $3.50…

jillian is selling boxes of cookies to raise money for her basketball team. the 10 oz. box costs $3.50, while the 16 oz. box costs $5.00. at the end of one week, she collected $97.50, selling a total of 24 boxes. the system of equations that models her sales is below.\n$x + y = 24$\n$3.50x + 5.00y = 97.50$\nsolve the system of equations. how many 10 oz. boxes were sold?\n6\n9\n12\n15
Answer
Explanation:
Step1: Express (y) in terms of (x)
From (x + y=24), we get (y = 24 - x).
Step2: Substitute (y) into the second equation
Substitute (y = 24 - x) into (3.50x+5.00y = 97.50). [ \begin{align*} 3.50x+5.00(24 - x)&=97.50\ 3.50x + 120-5x&=97.50\
- 1.5x&=97.50 - 120\ -1.5x&=-22.5\ x&=\frac{-22.5}{-1.5}\ x& = 15 \end{align*} ]
Answer:
15