70 Addition and Subtraction Concepts
Rigorous Problem Solving with the Concept of
Adding Doubles and Near Doubles 2
Kass and Dani are playing X Marks the Spot. In this game,
players roll a number, double it, and mark the sum on the
game board. Kass rolled 4, 2, and 5. Dani rolled 5, 3, and 4.Part A
Which set of numbers represents Dani’s sums?o 8, 6, 8
o 10, 6, 4
o 10, 5, 8
o 10, 3, 8
o 8, 4, 10
o 10, 3, 4
o 10, 6, 8Part B
Kirk says 6 + 7 = 13 because 6 + 6 = 12 and 12 + 1 = 13.
Do you agree with Kirk?
Why or why not?© 2016, Math Intervention: Grades 3–5, Jennifer Taylor-Cox, Routledge