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There are 21 NRICH Mathematical resources connected to Estimating and approximating, you may find related items under Calculations and numerical methods.
Broad Topics > Calculations and numerical methods > Estimating and approximatingWhich two items of fruit could Kate and Sam choose? Can you order the prices from lowest to highest?
How could you estimate the number of pencils/pens in these pictures?
Try some throwing activities and see whether you can throw something as far as the Olympic hammer or discus throwers.
This activity challenges you to decide on the 'best' number to use in each statement. You may need to do some estimating, some calculating and some research.
There are nasty versions of this dice game but we'll start with the nice ones...
Here is a chance to play a version of the classic Countdown Game.
This challenge is a game for two players. Choose two of the numbers to multiply or divide, then mark your answer on the number line. Can you get four in a row?
The Man is much smaller than us. Can you use the picture of him next to a mug to estimate his height and how much tea he drinks?
Lolla bought a balloon at the circus. She gave the clown six coins to pay for it. What could Lolla have paid for the balloon?
In this article for primary teachers, Ems outlines how we can encourage learners to be flexible in their approach to calculation, and why this is crucial.
How many teddies are in the jar? How many teddies could you fit in your classroom?
Four Go game for an adult and child. Will you be the first to have four numbers in a row on the number line?
Dicey Operations for an adult and child. Can you get close to 1000 than your partner?
Some Games That May Be Nice or Nasty for an adult and child. Use your knowledge of place value to beat your opponent.
How might you use mathematics to improve your chances of guessing the number of sweets in a jar?
What do you notice about the date 03.06.09? Or 08.01.09? This challenge invites you to investigate some interesting dates yourself.
Can you deduce the pattern that has been used to lay out these bottle tops?
Make an estimate of how many light fittings you can see. Was your estimate a good one? How can you decide?
Find the exact difference between the largest ball and the smallest ball on the Hepta Tree and then use this to work out the MAGIC NUMBER!
Mr. Sunshine tells the children they will have 2 hours of homework. After several calculations, Harry says he hasn't got time to do this homework. Can you see where his reasoning is wrong?
There are four equal weights on one side of the scale and an apple on the other side. What can you say that is true about the apple and the weights from the picture?