Part of our understanding of Place Value includes ‘rounding’.

We round numbers every time we go shopping, whenever we need to estimate size and quantity. It is a very important skill in life, it helps us to understand the value of an item.

It makes the number simpler while keeping it close to its actual value/size.

It allows us to estimate the total value of a collection of numbers, to feel certain our adding up is likely to be correct.

For example, if we know $4.50 is close to or can be rounded up to $5.00, we will easily recognise a mistake of a salesperson accidentally typing $45.00 into a cash register when recording the costs of items we want to buy!

Here’s some great examples from the nrich maths website to practice. The more fun you have with learning this concept, the more likely you will always remember it.

Enjoy,

Stephanie van der Schans

AST/Numeracy

To start…

There are three dice, each of them with faces labelled from 1 to 6.

When the dice are rolled they can be combined in six different ways to make a number less than 10 with two decimal places.

For example, if I roll a 2, a 3 and a 6, I can combine them to make 2.36, 2.63, 3.26, 3.62, 6.23 or 6.32.

Now round each of these numbers to the nearest whole number:

2.36 rounds to 2, 2.63 rounds to 3, 3.26 rounds to 3, 3.62 rounds to 4, 6.23 rounds to 6 and 6.32 rounds to 6.

Repeat for other rolls of the dice.

Can each of the six numbers round to the same whole number?

Can each of the six numbers round to a different whole number?

What if you had four six sided dice!

How many combinations would there be?

Can each of your numbers round to the same whole number?

Can each of your numbers round to a different whole number?

How could you present this convincingly, how can you be sure you have them all?