The sequence of diagrams below shows small black and small white squares in an arrangement to form large squares. [Figure 11.1] Diagram 1 Diagram 2 Diagram 3 The table below shows the numbers of black and white squares in each diagram. Diagram (n) 1 2 3 4 Black squares 5 13 25 White squares 4 12 24 Total number of black and 9 25 49 white squares

1. (a)For each diagram, how many more black squares are there than white squares?[1]
2. (b)On the table, complete the column for Diagram 4.[1]
3. (c)Write down an expression, in terms of n, for the total number of black and white squares in Diagram n.[1]

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