Answer :
The no: of textbooks Guillermo bought is 7
What are problem sums?
Issue with the internal transfer concept Sum questions involve subtracting from one unknown and adding to another, leaving the original total amount unaffected. It's also referred to as the Constant Total idea.
How do you teach children to problem sums?
Follow The Problem-Solving Process Step by Step.
Review Old Issues; Write Down What Doesn't Work; "3 Before Me"
Ask open-ended questions, promote grappling, place an emphasis on process over product, and use the techniques yourself!
Let the no: of notebooks be 2
The no: of textbooks are : 3+ (2*2)
=7
Hence, the total no: of books are 7
To know more about problem sums click the following link:-
https://brainly.com/question/25734188
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