Question

1. pedro is making chocolate chip cookies. he will put 15 chocolate chips in each cookie. he has 150 chocolate chips and will make at least 1 cookie.

circle the independent variable:
number of chips per cookie number of cookies made
circle the reasonable range:
making 1 - 10 cookies using between 15 and 150 chocolate chips

1. cynthia is selling candy bars for her class fundraiser. she has a box of 20 candy bars that she is going to sell for $2 each.

circle the independent variable:
number of candy bars sold amount of money earned
circle the reasonable domain:
selling 0 to 20 candy bars earning between $0 to $40

1. john is a custodian and can clean 5 classrooms in one hour. john can work up to 7 hours a day.

circle the dependent variable:
number of hours worked number of classrooms cleaned
circle the reasonable range:
cleaning between 0 and 35 classrooms each day working 0 - 7 hours per day

Explanation:

• Problem 3:
• The independent variable is the one that is changed or controlled. Here, the number of chips per cookie is fixed (\(15\)), and the number of cookies made affects the total chips used. So, the independent variable is "NUMBER OF COOKIES MADE".
• The range is the set of output values. Since each cookie has \(15\) chips and there are \(150\) chips, the number of cookies \(n=\frac{150}{15} = 10\) (maximum). And at least \(1\) cookie is made. So the reasonable range is "Making \(1 - 10\) cookies".
• Problem 4:
• The independent variable is what we can change freely. We can choose how many candy - bars to sell. The amount of money earned depends on the number of candy - bars sold (\(y = 2x\), where \(x\) is the number of candy - bars sold). So the independent variable is "NUMBER OF CANDY BARS SOLD".
• The domain is the set of input values. She has \(20\) candy - bars, so she can sell \(0\) to \(20\) candy - bars. So the reasonable domain is "Selling \(0\) to \(20\) candy bars".
• Problem 5:
• The dependent variable depends on another variable. The number of classrooms cleaned (\(y\)) depends on the number of hours worked (\(x\)) (\(y=5x\)). So the dependent variable is "NUMBER OF CLASSROOMS CLEANED".
• The range is the set of output values. If \(x = 0\), \(y = 0\); if \(x = 7\), \(y=5\times7=35\). So the reasonable range is "Cleaning between \(0\) and \(35\) classrooms each day".

Answer:

• Problem 3:
• Independent Variable: NUMBER OF COOKIES MADE
• Reasonable Range: Making \(1 - 10\) cookies
• Problem 4:
• Independent Variable: NUMBER OF CANDY BARS SOLD
• Reasonable Domain: Selling \(0\) to \(20\) candy bars
• Problem 5:
• Dependent Variable: NUMBER OF CLASSROOMS CLEANED
• Reasonable Range: Cleaning between \(0\) and \(35\) classrooms each day