2-Digit Number ± 1-Digit Number Within 20

Each question starts with a 2-digit number and adds or subtracts a 1-digit number using counting on or counting back.

Let’s solve
12 + 4 = ?
Bigger number in the headThen count on with fingers
Head number
12
Keep this number in your head.
Finger number
4
Show this many fingers.
Press Next to start counting!
We will move one jump at a time.
Write the answer
Count first, then check.
Number Tape
0 jumps used
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