a) Which of the following expressions indicates the number of squares when [[$ n $]] is the sequence number of the pattern?


Answer: The following expression indicates the number of squares:
[[$ 2n -1 $]] [[$ 3n - 2 $]] [[$ n + 4 $]] [[$ 4n - 3 $]] [[$ 2n + 4 $]]

b) Use the formula to calculate how many balls are in the pattern with order number [[$ 5 $]]. Check by drawing.



Answer: A pattern with order number [[$ 5 $]] has balls.