Lesson Notes By Weeks and Term v5 - Grade 5

Lesson Video

This page supports the lesson note with a companion video and a short classroom-ready summary.

For class groups and homework, share this lesson page so learners also get the summary, objectives, and full lesson context.

Performance objectives

• Solve word problems involving time calculations.
• Read and interpret temperature readings in degrees Celsius.
• Solve practical problems with length, mass, and capacity.
• Convert between different units of measurement.
• Solve measurement problems using all four basic operations.

Lesson summary

Time, temperature, and measurement are fundamental parts of our daily lives in South Africa. Understanding these concepts helps us plan our day, cook meals, understand the weather, build houses, and much more. From checking the time to catch a taxi to measuring ingredients for pap and vleis on a Sunday braai, these skills are essential. This week, we will be focusing on applying our knowledge of time, temperature, and measurement to solve everyday problems. This includes converting between units, calculating durations, and interpreting temperature readings.

Lesson notes

a)

Time: Time is measured in seconds, minutes, hours, days, weeks, months, and years. We use clocks and calendars to keep track of time.

Important Conversions: 1 minute = 60 seconds 1 hour = 60 minutes 1 day = 24 hours 1 week = 7 days Calculating Duration: Duration is the amount of time that passes between a start time and an end time. To calculate duration, we subtract the start time from the end time.

Example 1: Finding the Duration Thando starts playing soccer at 14:30 (2:30 PM) and finishes at 16:15 (4:15 PM). How long did he play?

Solution: End Time: 16:15 Start Time: 14:30 Duration = 16:15 - 14:30 = 1 hour and 45 minutes.

Therefore, Thando played soccer for 1 hour and 45 minutes.

Example 2: Finding the End Time Maria starts baking a cake at 09:45 (9:45 AM). The cake takes 50 minutes to bake. At what time will the cake be ready?

Solution: Start Time: 09:45 Baking Time: 50 minutes End Time = 09:45 + 50 minutes = 10:

3

5. Therefore, the cake will be ready at 10:35 (10:35 AM). b)

Temperature: Temperature is a measure of how hot or cold something is. In South Africa, we use degrees Celsius (°C) to measure temperature. Thermometers are used to measure temperature.

Understanding Thermometers: A thermometer has a scale with numbers. Read the number that the liquid (usually red or blue) reaches.

Temperature Differences: To find the difference between two temperatures, subtract the lower temperature from the higher temperature.

Example 1: Reading a Thermometer A thermometer shows a temperature of 28°

C. What is the temperature?

Solution: The temperature is 28 degrees Celsius.

Example 2: Finding the Temperature Difference The temperature in Johannesburg is 22°C, and the temperature in Cape Town is 15°

C. What is the difference in temperature?

Solution: Johannesburg Temperature: 22°C Cape Town Temperature: 15°C Temperature Difference = 22°C - 15°C = 7°

C. Therefore, the difference in temperature is 7 degrees Celsius. c)

Everyday Measurement Problems: We use different units to measure length, mass, capacity, and volume.

Length: The distance between two points. Units include millimetres (mm), centimetres (cm), metres (m), and kilometres (km).

Conversions: 1 cm = 10 mm 1 m = 100 cm 1 km = 1000 m Mass: The amount of matter in an object. Units include grams (g) and kilograms (kg).

Conversions: 1 kg = 1000 g Capacity/Volume: The amount a container can hold. Units include millilitres (ml) and litres (l).

Conversions: 1 l = 1000 ml Example 1: Length Conversion A table is 150 cm long. How long is it in metres?

Solution: 1 m = 100 cm 150 cm = 150 / 100 m = 1.5 m Therefore, the table is 1.5 metres long.

Example 2: Mass Problem A bag of potatoes weighs 5 kg. How many grams does it weigh?

Solution: 1 kg = 1000 g 5 kg = 5 1000 g = 5000 g Therefore, the bag of potatoes weighs 5000 grams.

Example 3: Capacity Problem A bottle contains 2 litres of juice. How many millilitres of juice are in the bottle?

Solution: 1 l = 1000 ml 2 l = 2 1000 ml = 2000 ml Therefore, the bottle contains 2000 millilitres of juice. Guided Practice (With Solutions)

Question 1: A bus leaves Johannesburg at 07:15 and arrives in Durban at 14:

0

0. How long was the bus trip?

Solution: End Time: 14:00 Start Time: 07:15 Duration = 14:00 - 07:

1

5. To do this subtraction, we need to "borrow" an hour from 14:00, making it 13:

6

0. Duration = 13:60 - 07:15 = 6 hours and 45 minutes.

Answer: The bus trip was 6 hours and 45 minutes long.

Question 2: The temperature at sunrise was 12°

C. By midday, it had risen to 27°

C. How much did the temperature increase?

Solution: Midday Temperature: 27°C Sunrise Temperature: 12°C Temperature Increase = 27°C - 12°C = 15°

C. Answer: The temperature increased by 15 degrees Celsius.

Question 3: A roll of fabric is 10 metres long. If I cut off 250 cm, how much fabric is left (in metres)?

Solution: Start Length: 10 m Cut Length: 250 cm Convert cm to m: 250 cm = 250 / 100 m = 2.5 m Remaining Length = 10 m - 2.5 m = 7.5 m Answer: There is 7.5 metres of fabric left.

Question 4: Sipho needs to fill a 5-litre bucket with water. He has a jug that holds 500 ml. How many times will he need to fill the jug to fill the bucket?

Solution: Bucket Capacity: 5 l Jug Capacity: 500 ml Convert litres to millilitres: 5 l = 5 1000 ml = 5000 ml Number of Jugs = 5000 ml / 500 ml = 10 Answer: Sipho needs to fill the jug 10 times. Independent Practice (Questions Only)

Nomusa starts her homework at 15:40 and finishes at 17:

1

0. How long did she spend doing homework? The temperature in Pretoria at 6 AM is 8°C. By 2 PM, it rises to 30°C. What is the temperature difference? A rectangular garden is 8 metres long and 5 metres wide. What is the perimeter of the garden? (Remember: Perimeter = 2 * (length + width)) A bottle of cool drink contains 1.5 litres. How many 250 ml glasses can be filled from the bottle? A bag of sugar weighs 2.5 kg. How many grams does it weigh?

A movie starts at 19:30 and lasts for 2 hours and 15 minutes. At what time will the movie end?