Mathematics 0580 · IGCSE · Sequences

Sequences — practice question

Shown here are the first four diagrams in a sequence: Diagram 1, Diagram 2, Diagram 3, Diagram 4, and Diagram 5 are displayed on a grid using the symbols O and X.
(a)[1]

Draw Diagram 5 on the grid.

(b)[2]

Complete the table shown below for Diagram 4 and Diagram 5.

(c)[1]

Find an expression, in terms of $n$, for the total count of Os and Xs in Diagram $n$.

(d)[1]

Find the total number of Os and Xs in Diagram 23.

(e)[1]

Describe the rule, in words, for extending the sequence for the number of Os.

Worked solution & mark scheme

This 6-mark question has a full step-by-step worked solution and mark scheme. One marking point: Accurate O/X grid shown

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