K-5 friendly lesson
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Complete the Sentence - Missing Pieces to 100

🧩 The puzzle has a hole! There is a number missing right in the middle of the math sentence. Use your detective skills to find it.

Lesson 4

Concept

Missing number problems look terrifying. **45 + ___ = 82**. What?! Don't worry, there are rules to crack the code. šŸŽÆ **The Missing Number Rules:** **Missing addition? ( 45 + ___ = 82 )** * Do the OPPOSITE! To find what is missing between 45 and 82, just subtract! * **82 - 45 = Target** -> (82 - 45 = 37). The missing number is 37! **Missing subtraction? ( 82 - ___ = 45 )** * If the piece missing is in the middle... just subtract! * **82 - 45 = Target** -> The missing number is 37! **Missing the START of a subtraction? ( ___ - 37 = 45 )** * If the very first, biggest number is missing, you have to ADD the two pieces back together to find out how big it used to be! * **45 + 37 = Target** -> The giant starting number was 82!

Try it

Crack the code! **Instructions:** Choose the right rule to find the missing piece. **Problem 1: 50 + ___ = 86** * Rule: Subtract the total minus the starting piece! (86 - 50 = ?). * Answer: ___ **Problem 2: 95 - ___ = 70** * Rule: Subtract! (95 - 70 = ?). * Answer: ___ **Problem 3: ___ - 25 = 40** * Rule: The massive start number is missing! Add the pieces back together! (40 + 25 = ?). * Answer: ___ **Problem 4: ___ + 38 = 90** * (Bonus Rule: Same as problem 1! Subtract from the total! 90 - 38 = ?). * Answer: ___