176 Multiplication and Division Concepts
Rigorous Problem Solving with the Concept of
Equal Products 1
Kayla and her Grandmother made holiday cookies. Each tray
had 35 cookies on it. When Grandmother took the sixth tray
out of the oven, Kayla asked, “How many cookies did we
bake?”Part A
Grandmother said, “We have 6 groups of 35, but let’s half the
groups and double the cookies in each group by putting the
trays in sets of 2.”
Which equation represents the equal products?o 6 x 35 = 2 x 70
o 6 x 35 = 12 x 70
o 6 x 35 = 12 x 35
o 6 x 35 = 3 x 70
o 6 x 35 = 12 x 7Part B
Joey said, “If there were 12 trays of 75 cookies we could
half the trays and double the cookies twice which would
be 3 x 300.” Do you agree or disagree with Joey?
Justify your answers with equations.© 2016, Math Intervention: Grades 3–5, Jennifer Taylor-Cox, Routledge