There are 9 NRICH Mathematical resources connected to Rounding, you may find related items under The Number System and Place Value.
Broad Topics > The Number System and Place Value > Rounding
Reasoned Roundinglive
Age 7 to 14
Challenge Level
Four strategy dice games to consolidate pupils' understanding of rounding.
Round the Dice Decimals 1
Age 7 to 11
Challenge Level
Use two dice to generate two numbers with one decimal place. What happens when you round these numbers to the nearest whole number?
Round the Three Dice
Age 7 to 11
Challenge Level
What happens when you round these three-digit numbers to the nearest 100?
Round the Dice Decimals 2
Age 7 to 11
Challenge Level
What happens when you round these numbers to the nearest whole number?
Round the Four Dice
Age 7 to 11
Challenge Level
This activity involves rounding four-digit numbers to the nearest thousand.
Rough Rectangle
Age 11 to 14 Short
Challenge Level
What is the smallest possible area that this rectangle could have?
Archimedes and Numerical Roots
Age 14 to 16
Challenge Level
The problem is how did Archimedes calculate the lengths of the sides of the polygons which needed him to be able to calculate square roots?
Route to Root
Age 16 to 18
Challenge Level
A sequence of numbers x1, x2, x3, ... starts with x1 = 2, and, if you know any term xn, you can find the next term xn+1 using the formula: xn+1 = (xn + 3/xn)/2 . Calculate the first six terms of this sequence. What do you notice? Calculate a few more terms and find the squares of the terms. Can you prove that the special property you notice about this sequence will apply to all the later terms of the sequence? Write down a formula to give an approximation to the cube root of a number and test it for the cube root of 3 and the cube root of 8. How many terms of the sequence do you have to take before you get the cube root of 8 correct to as many decimal places as your calculator will give? What happens when you try this method for fourth roots or fifth roots etc.?
NRICH is part of the family of activities in the Millennium Mathematics Project.