The challenge is to make 20 on your calculator using only six keys.
4  7    2  7  =  20 
5  +  7  +  8  =  20 
1  2  0  รท  6  =  20 
20 
How many different ways can you do this? You could try making a different total. Is there a limit to the possible totals? What if you could use seven keys or five keys?
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Previous Day  This starter is for 21 April  Next Day
30 − 10 = 20 
10 + 10 = 20 
Casio Classwiz CalculatorThere is currently a lot of talk about this new calculator being the best in its price range for use in the Maths classroom. The new ClassWiz features a highresolution display making it easier to view numerical formulas and symbols but it isn't a graphical calculator as such (it has the capacity to draw graphs on your smart phone or tablet, via a scannable QR code and an app). As well as basic spreadsheet mode and an equation solving feature you also get the ability to solve quadratic, cubic or quartic polynomial inequalities and the answer is given just as it should be written down, using the correct inequality symbols! This calculator has a highperformance processor and twice the memory of previous models ensuring speedy operation and superior computational power.more... 
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