Lesson 21: Practice Problems
Problem 1
Noah says that
is equivalent to , because the subtraction sign tells us to subtract everything that comes after . Elena says that
is equivalent to , because the subtraction only applies to .
Do you agree with either of them? Explain your reasoning.
Problem 2
Identify the error in generating an expression equivalent to
Problem 3
Select all expressions that are equivalent to
Problem 4 From Unit 6 Lesson 14
The school marching band has a budget of up to $750 to cover 15 new uniforms and competition fees that total $300. How much can they spend for one uniform?
Write an inequality to represent this situation.
Solve the inequality and describe what it means in the situation.
Problem 5 From Unit 6 Lesson 16
Solve the inequality that represents each story. Then interpret what the solution means in the story.
For every $9 that Elena earns, she gives
dollars to charity. This happens 7 times this month. Elena wants to be sure she keeps at least $42 from this month’s earnings. Lin buys a candle that is 9 inches tall and burns down
inches per minute. She wants to let the candle burn for 7 minutes until it is less than 6 inches tall.
Problem 6 From Unit 4 Lesson 3
A certain shade of blue paint is made by mixing