Lesson 6
Subtracting Rational Numbers
Let's bring addition and subtraction together.
Problem 1
Write a sentence to answer each question:
-
How much warmer is 82 than 40?
-
How much warmer is 82 than -40?
Problem 2
-
What is the difference in height between 30 m up a cliff and 87 m up a cliff? What is the distance between these positions?
-
What is the difference in height between an albatross flying at 100 m above the surface of the ocean and a shark swimming 30 m below the surface? What is the distance between them if the shark is right below the albatross?
Problem 3
A company produces screens of different sizes. Based on the table, could there be a relationship between the number of pixels and the area of the screen? If so, write an equation representing the relationship. If not, explain your reasoning.
| square inches of screen | number of pixels |
|---|---|
| 6 | 31,104 |
| 72 | 373,248 |
| 105 | 544,320 |
| 300 | 1,555,200 |
Problem 4
Find each difference.
-
\((\text-5) - 6\)
-
\(35 - (\text-8)\)
-
\(\frac25 - \frac35\)
-
\(\text-4\frac38 - (\text-1\frac14)\)
Problem 5
A family goes to a restaurant. When the bill comes, this is printed at the bottom of it:
| Gratuity Guide For Your Convenience: 15% would be $4.89 18% would be $5.87 20% would be $6.52 |
How much was the price of the meal? Explain your reasoning.
Problem 6
Which is a scaled copy of Polygon A? Identify a pair of corresponding sides and a pair of corresponding angles. Compare the areas of the scaled copies.
