Solving Comparison Word Problems Using Subtraction

Khan Academy

This video guides students through solving a comparison word problem involving dominoes and a six-sided die. The narrator demonstrates how to decipher the language of the problem—specifically the phrase "42 more spots than"—to determine the correct mathematical operation. Rather than simply seeing the word "more" and adding, the video emphasizes critical thinking and logic to realize subtraction is required. The video covers key themes such as reading comprehension in mathematics, identifying knowns and unknowns, and the relationship between addition and subtraction (inverse operations). It models how to set up an equation with a variable (represented by a question mark) and how to rearrange that equation to solve for the answer. For educators, this video is an excellent resource for addressing the common "keyword trap" where students blindly apply operations based on words like "more" or "less." It provides a clear visual model of how to translate text into a mathematical sentence and demonstrates standard vertical subtraction without regrouping.