1253
this one goes out to the arts & humanities (mander.xyz)
submitted 2 years ago by to c/science_memes@mander.xyz
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[+] -9 points 2 years ago (1 child)

Well you should memorize those anyway. It's useful all your life for easy calculation. If you want 7 items and they cost $3.50 each, it's between $21 and $28.

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  • [–] 4 points 2 years ago (2 children)

    I check on the calculator I have with me at all times. It's $24.50

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  • [–] 2 points 2 years ago* (1 child)

    I calculated it in my head without memorising all the multiplication tables. I just realised that 7*3.5 is equal to (7*5+7*2)/2. And that 49/2 is equal to 40/2+9/2. Easy peasy. This is why I failed second grade math, because multiplication tables are only useful for doing operations a few seconds faster.

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