The numbers on blue shapes are the sums of the two hidden numbers on red circles at the ends of the lines. What are the hidden numbers?
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Topics: Starter  Arithmetic  Problem Solving  Puzzles  Simultaneous Equations
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Previous Day  This starter is for 21 January  Next Day
Note to teacher: Doing this activity once with a class helps students develop strategies. It is only when they do this activity a second time that they will have the opportunity to practise those strategies. That is when the learning is consolidated. Click the button above to regenerate another version of this starter from random numbers.
How difficult would the Pentadd puzzle be without the diagram? Imagine five numbers, randomly chosen, are added together in pairs to produce the following ten sums in no particular order. Can you figure out what those five numbers were?
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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