Well done! You are right.
But we don’t teach elementary school children how to form equations. It’s cognitively too abstract for them.
Of course, if a precocious kid were to solve this problem using your method, he would be awarded full marks.
I wonder what was the success rate...
Just watched the video... this is like solving equations without calling them equations... not sure if this way is easier or more intuitive :)
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for the record, my work started with the two bottom lines, and then the two lines above. I don't explain my work, but a math teacher like you will recognize what's going on.
this is simply what came to me. maybe we should teach elementary children how to form equations.
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