Year 5 - Rates

by Teacher Amira

​Our learning objectives:

​Pupils will be able to:

​1. Understand and interpret examples of rate.

​2. Interpret rate as the total amount divided by the number of units.

​3. Calculate and apply rates in daily transactions.

​Source: Yes! Mathematics 5B Teacher's Guide Book

Now, count the number of times your heart beat in a minute.

​Steps:

​1. Get a timer (or anyone to time)

​2. Touch your wrist.

​3. Start counting the number of heart beat in one minute.

​4. Write down the number on a piece of paper.

​Record your time as:

​

​______ beats per minute

The number of heart beats per minute is an example of our topic today, RATE.

​Fact:

​Your heart will beat about 115,000 times each day

Multiple Choice

Razif took a walk round a field.

He counted that his heart beat 80 times in a minute after the walk.

Which is the correct way to tell the rate?

• Razif's heart rate was 80 beats per minute after his walk.

• Razif's heart rate was 80 minutes per beat after his walk.

• Razif's heart beat 80 minute after his walk.

We can calculate rate by taking the total amount divided by the number of units.

​Example 1:

​A printer prints 750 pages in 10 minutes.

​

​10 minutes - 750 pages.

​

​How many pages can the printer print in 1 minute?

​~ in 1 minute =

​

​The printer can print 75 pages in 1 minute.

​

​

​So, we can say that:

​The printer prints at a rate of 75 pages per minute. This is the unit rate.

​Example 2:

​Arifah ran 8 km in 2 hours. How many kilometres did Arifah run per hour?

​

​Working:

In 2 hours - 8 km

​

​In 1 hour -

​

​Answer:

​Arifah ran 4 km per hour.

Multiple Choice

A car travels at 320 km for 4 hours.

How many km did the car travel in one hour?

​Example 3:

​Water flows from a tap at a rate of 50 litre per minute.

​At this rate, how many litres of water flows from the tap in 4 minutes?

​

Rate = 50 litre per minute

​Number of Units = 4 minutes

​Total amount = ?

​

​Answer: 200 litre of water flows from the tap in 4 minutes.

Multiple Choice

Mr. Ali parked his car at a car park for 3 hours. 

The parking rate was $2 per hour. 

At this rate, how much did Mr. Ali have to pay?

Poll

That's all for today!

What do you think of this topic?