Mathematics / Year 5 / Number and Algebra / Number and place value

Curriculum content descriptions

Use estimation and rounding to check the reasonableness of answers to calculations (ACMNA099)

Elaborations
  • recognising the usefulness of estimation to check calculations
  • applying mental strategies to estimate the result of calculations, such as estimating the cost of a supermarket trolley load
General capabilities
  • Numeracy Numeracy
ScOT terms

Rounding,  Accuracy and precision

Video

MathXplosion, Ep 16: It's an estimate, not a guess!

An approximation is the nearest estimate without having the precise size or measurement of something. See how accurate estimates are made in logical ways using information about many things in our everyday lives.

Video

MathXplosion, Ep 5: Measure a tree without using a ladder

What do you do when you need to measure a length, height or distance but don't have a ruler or some other measuring instrument? You can compute linear measurements with surprising accuracy using indirect measurements, proportions and estimations. Learn a nifty trick to measure a tree from a distance.

Video

Mixed Up Maths, Ep 6: Maths saves lives

Can maths really help to save lives? In this clip we see some real life applications of mathematics. Some are about helping to save lives others are about how maths can be useful. What do Florence Nightingale and WHO, the World Health Organisation have in common?

Video

MathXplosion, Ep 3: How many heads tall are you?

What are non-standard measurement units? Did you know we can reliably use objects in the real world, including our own body parts, to measure things? This concept of anthropometry, the ratios of body measurements, was first proposed by Leonardo da Vinci.

Video

Rounding whole numbers: 2

This is a video demonstration of rounding a whole number to the nearest thousand. In the commentary, the presenter explains the thinking behind the process of rounding such numbers and presents a visual representation of rounding whole numbers using a number line. Practice questions with answers are included, and hints ...

Interactive

My American farm: app for iPad

This iPad app contains a selection of games with an agricultural theme. At the conclusion of the activities, fun farm facts or information are provided (some of these facts can be read aloud by selecting a volume icon). The games encompass a range of things important to farming life including farming equipment, careers ...

Interactive

Cassowary ecology quiz

Explore facts about the life of cassowaries: physical characteristics; diet; habitat; life cycles; and locations. Interact with graphs to see how much people can help cassowaries. Work through ecology notes and resources. Answer questions as you go; express your answers as fractions. This learning object is one in a series ...

Interactive

MoneySmart: helping out

This is an activity about making choices to raise money for imaginary animals called gumbutangs. Their habitat is being eradicated and something must be done to save them. The user's first choice is between two websites, one a trusted one, the other a scam site. Then they are given choices about how to raise money for the ...

Interactive

Summing Decimals

An interactive resource in which students learn how to add and subtract numbers that have up to two decimal places.

Interactive

The foul food maker: go figure

This tutorial is suitable for use with a screen reader. It explains how the use of simple words can describe the likelihood of everyday events. How likely is an event: certain, likely, equal chance, unlikely or certainly not? Answer some questions using these words and then build your own examples. Learn how to describe ...