Exploring Integers

Learning Goals

Understand that:• Integers are numbers that can be created from

subtraction patterns.• Integers appear in many areas of the real

world.

• Temperature is measured in degrees Celsius (˚C). Water freezes at 0˚C.

• On a typical summer day in Saskatoon, the temperature might be 24 ˚C above zero.

• A temperature greater than 0 ˚C is positive. We write 24 ˚C. We say: twenty-four degrees Celsius.

• On a typical winter day in Saskatoon, the temperature might be 18 degrees Celsius below zero.

• A temperature less than 0 ˚C is negative. We write: -18 ˚C. We say: minus eighteen degrees Celsius

Explore

Altitude is the vertical distance above sea level. It is usually measured in meters. For every 150m above sea level, the temperature decreases about 1 ˚C.

Kayla and Sydney are mountain climbing. They begin climbing at an altitude of 1000m. The temperature is 6 ˚C. The table shows the altitude changes.

Altitude (m) Temperature (˚C)

1000 6

1300

1600

1900

2200

2500

Continue the table for altitudes. Write a pattern rule for the temperatures.

• Numbers such as 24 and -18 are integers.

• You can represent integers on a number line. The number line may be vertical or horizontal.

• A thermometer is a vertical number line.

• You have horizontal number lines to compare and order whole numbers. We extend the number line to the left of 0 to show negative numbers.

• We use integers to represent quantities that have both size and direction.

• Mark spent $25. This can be represented as -$25.

• Jean walked 5 steps forward. This can be represented as +5 steps or 5 steps.

• A scuba diver swam to a depth of 50 m. This can be represented as -50m.

• If no sign is written, the integer is positive.

Homework

Grade 5 – P22 – Questions 1-4

Grade 6 – P22 – Questions 1-4 & P26 Questions 1-2