Which of the numbers from one to twenty can you make with the digits:
4, 5, 6 and 7
You can use any mathematical operations but you must use all four digits once in each calculation.
Example 20 = 4(7  6) x 5
Topics: Starter  Arithmetic  Mental Methods  Problem Solving
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Previous Day  This starter is for 15 April  Next Day
4, 5, 6 and 7
1 = 
11 = 
There are many different answers. These are not the only ones
1 = (7  6)(5  4) 
11 = 75  64 
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Teacher, do your students have
access to computers? 

Here a concise URL for a version of this page without the comments.
Here is the URL which will take them to a different type of mental maths activity.
Here is the URL which will take them to a similar 4 digit calculation challenge.