If all the students in this room shook hands with each other, how many handshakes would there be altogether?
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Topics: Starter  Investigations  Number  Problem Solving
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No. of Students  No. of Handshakes 
1  0 
2  1 
3  3 
4  6 
5  10 
6  15 
7  21 
8  28 
9  36 
10  45 
11  55 
12  66 
13  78 
14  91 
15  105 
16  120 
17  136 
18  153 
19  171 
20  190 
21  210 
22  231 
23  253 
24  276 
25  300 
26  325 
27  351 
28  378 
29  406 
30  435 
31  465 
32  496 
Can you find a formula for the number of handshakes given the number of students?
If instead of handshakes, each student in the room gave every other student a present, how many presents would be given?
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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... 
Teacher, do your students have
access to computers? 

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