Final Answer
To earn a profit of more than $50, Stefan must sell more than
cups of lemonade.
Step-by-step explanation:
Stefan's profit can be calculated using the equation
The revenue from selling
cups of lemonade is
and the cost is $6.50. Therefore, the profit equation is
To find the number of cups needed to earn a profit of more than $50, set the profit greater than $50 and solve for

![\[ 1.25x - 6.50 > 50 \]](https://img.qammunity.org/2021/formulas/mathematics/high-school/n59jqw1grsuea8f8ksb1e78kson2u4znck.png)
![\[ 1.25x > 56.50 \]](https://img.qammunity.org/2021/formulas/mathematics/high-school/hbl1evceqcgcamybjdtnw059o6scuw5aa3.png)
![\[ x > (56.50)/(1.25) \]](https://img.qammunity.org/2021/formulas/mathematics/high-school/gh5qtfmzwmbqs6ilvth2a3uehl142vj4ly.png)
![\[ x > 45.2 \]](https://img.qammunity.org/2021/formulas/mathematics/high-school/zyqznm1ktehnzvky2qxrvrwpppbxd28rul.png)
Since \( x \) represents the number of cups, and cups cannot be in fractions, Stefan needs to sell more than 45 cups to achieve a profit of more than $50. Therefore, the final answer is \( x = 46 \) cups.
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Question 2:
Final Answer:
Stefan needs to deposit
weeks with $1.25 each week to have a balance of more than $50 in his savings account.
Step-by-step explanation:
The balance in Stefan's savings account can be expressed by the equation
the weekly deposit is $1.25, and the balance should exceed $50:
![\[ 6.50 + 1.25x > 50 \]](https://img.qammunity.org/2021/formulas/mathematics/high-school/g69pqbe2dypmkg31zwwd2txz5mvw5llllu.png)
![\[ 1.25x > 43.50 \]](https://img.qammunity.org/2021/formulas/mathematics/high-school/bnwo8ibmg5jldp7hd8fl46nygtwoj4bmbb.png)
![\[ x > (43.50)/(1.25) \]](https://img.qammunity.org/2021/formulas/mathematics/high-school/yuj13wzdp7txc0dfhabeyy4l4hy6rkjgla.png)
![\[ x > 34.8 \]](https://img.qammunity.org/2021/formulas/mathematics/high-school/n3aoczywmz5p5cqn2sxni87o2bizkgjiun.png)
Since
represents the number of weeks, and weeks cannot be in fractions, Stefan needs to deposit for more than 34 weeks to have a balance of more than $50. Therefore, the final answer is
weeks.