Math Intervention 3–5 Grade

204 Multifaceted Number Concepts

Rigorous Problem Solving with the Concept of

Prime and Composite Numbers 1

The game Prime Time requires players to draw factor trees for

composite numbers.

Joey drew this factor tree for the number 42.

Part A

Which numbers in Joey’s factor tree are composite?

o 42, 6, 7, 2, 3, 7

o 42, 6

o 2, 3, 7

o 6, 7, 2, 3

Part B

Is there another way to draw a factor tree for the number 42?

If so, draw it.

42

67

237

Part C

If there are 42 guests and we need to arrange an even number

of chairs at each table, how many different ways could we

arrange the chairs?

© 2016, Math Intervention: Grades 3–5, Jennifer Taylor-Cox, Routledge