Can you multiply two digit numbers without a calculator?

[Shrimpenjoyer]

Yes, but need to write it down a paper

Yes can calculate it in my head

No I can't

[WindAtMyBack]

There was no such thing as calculators when I learned math, so yea. If I wanted to bother with it I could multiple four digit numbers, and maybe five digit numbers. I might still be able to take square roots and cube roots of five digit numbers - but probably not since I'm out of practice.

As the saying goes, use it it lose it. If you use calculators for simple stuff, you aren't doing yourself any favors. It's the mental equivalent of a being a couch potato and not getting any exercise.

[slatyb]

Yes, quite rapidly. Once I was in a business meeting and the director said he was watching some game show and the contestants were asked "What's 37 x 42?" and one answered instantly. I wanted to shout "1554" but did not. His point was rather stupid -- work smarter, not harder. In software development the way to get a high-quality product faster is to decrease the time between code and test -- ideally down to seconds.

How did I do it? I refactored 37 x 3 x 14 = 111 x 14.

[Shrimpenjoyer]

That's a smart way.
I went the typical way and it took about 5 seconds to get it

[slatyb]

It's easy if you know that 37x3 = 111; similarly 67x3 = 201 so 67x42 = 2814.

[Simslover92]

I can't remember every one of them but I do remember some like 12x12 is 144 or 9x9 is 81.

Multiplying random numbers beyond the basic ones is harder like 21x32. But it would be...672
21
32

42
+63
672

[Shrimpenjoyer]

9×9 would be multiplying single digit

[Simslover92]

Oh yeah that's true

[CupcakeTheDestroyer]

That’s a good chunk of my job, so yeah

[Shrimpenjoyer]

What's your job

[CupcakeTheDestroyer]

Food service

[exitseven]

yes I can do it in my head It might take s few seconds.

[Zack-Bann]

I could do 12 times 15 = 180


But I would struggle with 67 times 82


It really depends on how big the number is

[Ms_Facesitter]

Yes but I might think out loud.

[Jeff51]

If its easy but need a calculator

[Shrimpenjoyer]

Not quite getting what you mean

[Jeff51]

If just 2 numbers yes, I know my times tables but, Example- 45×7. I need a calculator.

[Shrimpenjoyer]

Ah ok

[Drumlin2001]

I'd give it a go.

[jahaims]

Duh.