Vocabulary
numbers that are added together
What are addends?
Estimate the perimeter of a rectangle that has a length of 13.2 and a length 4.9
Write an equation to model your work.
What is
13 + 13 + 5 + 5 = 36
20.47 + 10.52 =
What is 20.5 + 10.5 = 31?
0.82 + 4.21 =
What is 5.03?
16.82 - 5.23 =
What is 11.59?
numbers that are easy to calculate mentally.
what are compatible numbers?
Estimate the perimeter of a rectangle that has a length of 57.59 and a width of 36.48.
Write an equation to model your work.
3.67 + 2.30 =
What is 3.7 + 2.3 = 6?
6.9 + 2.8 =
What is 9.7?
17.8 - 4.91=
What is 12.89?
Changing the order of the addends doesn't change the sum.
What is the commutative property?
What is the (exact) perimeter of a rectangle with a length of 65.22 and a width of 10.74?
What is 151.92?
24.82 - 4.02 =
What is 24.8- 4.0 = 20.8?
52 + 36.78 =
What is 88.78?
7.09 - 3.6 =
What is 3.49?
When adding three or more numbers, the grouping of the addends doesn't change the sum.
What is the associative property?
What is the (exact) perimeter of a rectangle with a length of 8 and a width of 7.95?
What is 31.9?
5.53 + 3.48 =
What is 5.5 + 3.5 = 9?
1.33 + 12.3 =
What is 13.63?
$21 - $10.95 =
What is $10.05?
An operation that undoes answer operations.
Hint: opposites
What is an inverse operation?
What is the perimeter of a square that has a side length of 43.57?
What is 174.28?
10.52 - 5.38 =
10.5 -5.4 = 5.1?
7.2 + 3.96 + 8 =
What is 19.16?
80 - 72.37 =
What is 7.63?