5
+1
6
+13
1
+15
1
+18
10
+4
5
+13
5
+1
2
+16
5
+1
5
+11
4
+15
10
+8
6
+12
8
+10
5
+12
2
+13
10
+2
6
+2
10
+9
10
+6
Practice addition within 20 with free printable worksheets. Uniquely generated — reinforce key math skills with every set.
Frequently Asked Questions
How do I use this Addition Within 20 Hard Worksheets worksheet?
Print the worksheet and complete the problems. Each set number generates a unique arrangement. Use the same set number for all students in a class for consistent assessment.
Is there an answer key?
Yes — every worksheet includes a complete answer key. Print it separately or view it on screen.