Inequalities and Number Comparisons

Mr. Wooly provides a review of inequalities for LC Middle School students, covering basic concepts, solving techniques, and real-world applications. The video includes practice problems and solutions, emphasizing the importance of flipping inequality signs when multiplying or dividing by negative numbers. Students are reminded to adhere to video guidelines and prepare for their upcoming test.

Which of the following statements is true about negative numbers compared to positive numbers?

• Negative numbers are less than positive numbers.

• Negative numbers are not comparable to positive numbers.

• Negative numbers are greater than positive numbers.

• Negative numbers are equal to positive numbers.

If you subtract 4 from both sides of the inequality -3 < 1, what is the resulting inequality?

• -3 > -7

• -7 > -3

• -3 < -7

• -7 < -3

What happens to the inequality sign when you multiply both sides of an inequality by a negative number?

• The inequality sign remains the same.

• The inequality sign flips direction.

• The inequality sign becomes an equal sign.

• The inequality sign disappears.

Solve the inequality: x + 7 ≤ 21. What is the value of x?

• x ≤ 14

• x ≥ 14

• x < 14

• x > 14

In the problem of determining the dimensions of a fence, if the width is w, what is the expression for the length?

• w/9

• 9w

• w - 9

• w + 9

Kyle can spend at most $45 on sandwiches and chips. If he already spent $11 on chips, how many sandwiches can he buy if each costs $4.25?

• 8 sandwiches

• 10 sandwiches

• 6 sandwiches

• 12 sandwiches

Noah wants to maintain at least $175 in his bank account. If he starts with $400 and withdraws $20 weekly, how many weeks can he continue withdrawing?

• 10 weeks

• 12 weeks

• 11 weeks

• 13 weeks

For a phone plan, if the first option costs $23 plus $0.15 per minute and the second option is $75 for unlimited minutes, for how many minutes is the first option cheaper?

• 500 minutes

• 300 minutes

• 400 minutes

• 346 minutes

What is the inequality to represent the situation where Dave's first phone plan option is cheaper than the second?

• 0.15m + 23 < 75

• 0.15m + 23 > 75

• 0.15m + 23 = 75

• 0.15m + 23 ≤ 75

If Dave can talk for up to 346 minutes on the first phone plan option, what is the maximum number of minutes he can use?

• 346 minutes

• 350 minutes

• 360 minutes

• 340 minutes