Question

Which of the following is the best algebraic expression for the sequence 3, 6, 9, 12

Answer 1

$\bf \stackrel{3\cdot 1}{3}~~,~~\stackrel{3\cdot 2}{6}~~,~~\stackrel{3\cdot 3}{9}~~,~~\stackrel{3\cdot 4}{12}~\hspace{10em}3\cdot x\implies 3x$