Adding 10 & 100 to a number
What is 20+10
30
What are they skip counting by?
5,10, 15,20,25,30
5's
what is 10+15
25
What is 15-12
3
What do we call the answer to an addition equation?
Sum
What is 30+100
130
What are they skip counting by?
30, 40, 50, 60,_____,80, 90
What is 21+43
64
What is 44-22
22
What do we call the answer to a subtraction equation?
Difference
What is 84+10
94
What is the missing number?
8, 12, 16,___,24, 28.
20
What is 18+82
100
What is 34-18
16
What are strategies for adding two-digit numbers involving breaking numbers apart using place value and joining tens and ones in either order called?
regrouping
What is 120+100
220
What are they skip counting by?
15, 25, 35, 45, 55.
10's
What is 63+29
92
What is 81-36
45
One way to add two-digit numbers is to break the numbers into tens and ones, add the tens and add the ones in either order, and then add these _____ sums to find the total. What kind of sums?
partial
What is 116+10
126
What is the missing number?
14, 21, 28,____,42, 49.
35
What is 14+66
80
What is 92-89
3
When subtracting two-digit numbers, you can subtract the tens and then subtract the ones by making a 10. What is this method called ?
Partial differences