Why it happens: Two equal trays are two equal groups, so we double the 18 cupcakes of one tray.
Q2.
c) Today she has received a special order. She has made 108 cupcakes. How many trays has she baked?
Answer
Both trays filled: 3 rows of 6 cupcakes in each tray.
She has baked 6 trays.
One tray holds 18 cupcakes, so we find 108 ÷ 18. Take away trays of 18: 18, 36, 54, 72, 90, 108 Count them: 1, 2, 3, 4, 5, 6 Check: 6 × 18 = 108 ✓
Tip: Skip counting in 18s is easy if you jump in twos of trays: 2 trays = 36, 4 trays = 72, 6 trays = 108.
Q3.
d) She has another square baking tray. She can bake 36 mini cupcakes in such a tray. Complete the arrangement below.The square baking tray from the book, with the first row and the first column started. Number of columns: _______ Number of cupcakes in each column: _______ Multiplication statement _______
Answer
The square baking tray as it is printed in the book.
The tray is a square, so it has the same number of rows and columns.
The square tray filled with 36 mini cupcakes.
Number of columns: 6 Number of cupcakes in each column: 6 Multiplication statement: 6 × 6 = 36
Why it happens: The book has drawn 6 cupcakes along the top and 6 down the side. A square tray must have equal rows and columns, and 6 sixes make 36.
Q4.
Find different ways of arranging the following numbers of cupcakes in rows and columns in your notebook. 36, 8, 12, and 24
Answer
For each number, look for two numbers that multiply to give it. Each pair is one arrangement.
Cupcakes
Ways (rows × columns)
36
1 × 36, 2 × 18, 3 × 12, 4 × 9, 6 × 6
8
1 × 8, 2 × 4
12
1 × 12, 2 × 6, 3 × 4
24
1 × 24, 2 × 12, 3 × 8, 4 × 6
Every pair can also be turned around, like 12 rows of 3 instead of 3 rows of 12.
Sample answer: 24 cupcakes can be set in 4 rows of 6, or 3 rows of 8, or 2 rows of 12, or 1 long row of 24.
Why it happens: An array works only when every row holds the same number. So the two side numbers must multiply to give the total.