I need help with everything in pink, I did these notes during class so they might not be the best handwriting just ask me if you need me to clarify anything.
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we have
estimated the quotient
41.9/8.6
41.9 is less than 45 ------> round down 40
8.6 is greater than or equal to 8.5 ----->round up 9
therefore
41.9/8.6=40/9