Regrouping
Solve 17-9=? by regrouping.
17-9=8
Use a number line to solve! 17-8=?
17-8=9
How can you decompose a number to subtract? 49-22=?
49-22=? 22= [20+2]
49-20=?
29-2=27
Solve 27-19=? by adjusting with friendly numbers.
27-19=?
+3 +3
30-22=8
OR
+1 +1
28-20=8
Solve 37-19=? by using base ten short hand.
37-19=18
Solve 26-19=? by regrouping.
26-19=7
Create a number line. Solve 17-11=?
17-11=6
Solve 39-16=? by decomposing.
39-16=? 39-(10+6)=?
39-10=29
29-6=23
Solve 31-19=? by adjusting.
31-19=
-1 -1
30-18=12
OR
+1 +1
32-20=12
Solve 48-39=? by using base ten short hand.
48-39=9
Brian's haircut takes 32 minutes. Ben's haircut takes 19 minutes. How many more minutes does Brian's haircut take than Ben's haircut? Solve by regrouping.
32-19=13
Create a number line. Solve 30-17=?
30-17=13
Solve 76-48=? by decomposing.
76-48=? 76-(40+8)=?
76-40=36
36-8=28
Solve 57-28=? by adjusting.
57-28=?
+3 +3
60-31=29
OR
+2 +2
59-30=29
Solve 54-49=? by using base ten short hand.
54-49=5
The barber has a box of 43 combs. He takes 26 combs out of the box. How many combs are still in the box? Solve by regrouing.
43-26=17
Create a number line. Solve 43-24=?
43-24=19
Solve 55-25=? by decomposing.
55-25=? 55-(20+5)=?
55-20=35
35-5=30
Solve 79-31=? by adjusting.
79-31=?
+1 +1
80-32=48
OR
-1 -1
78-30=48
Solve 68-39=? by using base ten short hand.
68-39=29
Ms. Becker has 78 treats for Lola. Lola hides 29 of the treats. How many bones are left for Ms. Becker to put away?
78-29=49
Create a number line. Solve 59-43=?
59-43=16
Solve 78-29=? by decomposing.
78-29=? 78-(20+9)=?
78-20=58
58-9=49
Solve 97-29=? by adjusting.
97-29=?
+3 +3
100-32=68
OR
-2 -2
95-27=68
Solve 92-49=? by using base ten short hand.
92-49=43