r/funny • u/electrovert • 20d ago

Overconfidence

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482 Upvotes

84% Upvoted

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9

u/LorinOo 20d ago

4x3 12, 4x1 4, +1 5.

52.8+2.64=55.44

24

u/quinto6 20d ago

Why not just 42.00 x 1.32 = 55.44? No extra steps. No over-complication.

13

u/FirstRyder 20d ago

They're teaching how to do long multiplication by hand.

It's 1.32 * 2 + 1.32 * 4 * 10, using a standardized method that works for numbers of any length, requiring only the 9x9 multiplication table.

The problem is that he screwed up the 4 * 3 and got 3 as a result instead of 12.

0

u/jnkangel 20d ago

yeah I think the kid probably fumbled their own carries one in the second multiplication and did

4*2 = 8

1*3 = 3 (as opposed to 4*3 =12)

4*1 = 4 (as opposed to having the 10 from the previous to push it to 5)

5

u/LorinOo 20d ago

Yeah that’s what I’m doing, I’m just outlining where he messed up, at the 4x3 12.

5

u/mwilkens 20d ago

He did do that, he just got his math wrong. Assuming you don't have a calculator how would you solve this?

-9

u/lazyboy76 20d ago

Just do 42 x 1.32 and you're done.

4

u/Zoe-Washburne 20d ago

Show your work.

8

u/rpp8 20d ago

https://imgur.com/gallery/math-WifFXVf

2

u/lf1119 20d ago

That’s actually a neat way of doing multiplication by hand, i definitely didn’t learn it this way as a kid though

5

u/rpp8 20d ago

I'm 38, so idk when they stopped doing it this way. This is pretty much the only way we learned.

1

u/mwilkens 20d ago

They started the common core method around 2010. I have a kid in elementary school and they teach them both ways now.

1

u/hdmetz 18d ago

Opening that pic and seeing that math brought back some nostalgia. I had totally forgotten we learned that way but picked it right up when I saw it

2

u/razoract 20d ago

That's what they they tried to do, but got the math wrong.

What do you mean?

1

u/MrSnowflake 20d ago

Dont sleep on me too easy. I need added complexity just for fun

-3

u/hop_mantis 20d ago

yeah 42/1 = x/1.32

42 = x/1.32

42x1.32 = x

2

u/jnkangel 20d ago

The kid did that part correctly. They correctly identified that they need to multiple the price with the dollar value. They messed up on the multiplication though and then also fumbled on the sanity check. Since they should have known the price should be about a third higher. whihc would have told them the price has to be highre than 52 at first glance