Math Olympiad Question | Calculate Without Calculators | You should be able to solve this

How to solve this math question? The most wonderful method you've ever seen!

[mikaeeldolie]

forty years ago in school we had to do this in our heads
5 x 2 = 10
so 5^5 x 4^7 = 5^5 x 2^14 = (10)^5 x 2^9 = 100, 000 x 512 = 51, 200, 000

[MitchBurns]

20 isn’t all that nice of a number. It’s better to turn the 4^7 into 2^14, then 2^5*2^9. Then you can say it’s 10^5*2^9. I’ve got all the powers of 2 memorized so I just count them out on my fingers to find 2^9 is 512, then just add 5 Zeros to get 51, 200, 000. Easy.

[Kevin-S]

This is easier to do without algebra, but instead picturing the exponents converted to multiplication

[Metal_dead]

What are you doing so long in this video?
5^5*4^7= 5^5*2^14= I'm doing this while sitting on the toilet this morning, half of the time I was looking for ^ on my phone. And the video didn't end while I wrote it.

[jonathanryals]

I did it like this: split it into 20^5×16, then factored it again to 2^9×10^5. So it is 512 with 5 zeroes or

[georgesbv]

No one that publishes "Olympiad problems" mentions if they are 5th grade or lower

[olivierhabineza]

What I have found from my head is that we have millions.

[MrMousley]

How about getting a good old fashoned piece of paper and a pen and working it out ?
5 x 5 x 5 x 5 x 5 = 3125
4 x 4 x 4 x 4 x 4 x 4 x 4 = 16384
3215 x 16384 =
Which .. to confirm your ''answer'' .. is 512 with 5 zeros after it !
. and I did it in less than half the time of your method.

[lowkey_maniac_]

Instead of writing 5.12×10⁷, can i write your voice is so soothing

[jim]

20^5*4^2 by inspection. 2^5*10^5*16 = 32*100, 000*16 = 51, 200, 000

[gobinddas]

I am from Nepal but your big fan ❤ i didn't understand your voice but i understand your math olympied questions 🇳🇵🇳🇵🇳🇵

[Archik]

Olympiad Question? Resolved it in my head.

[gajarer]

This is pure objective type question very easy type

[kurosan]

This can be solved in head within seconds
However, I must admit I made a mistake and instead of multiplying them just added them first

[gnatius]

не совсем понял смысл последнего упрощения, если вопрос стоял про результат, а не про именно упрощение...

[mariocaroselli]

Gli esponenti si differenziano di due cifre numero pari i dispari tre moltiplicare il pari per complementare la cifra solutiva.

[broombak]

It would be better if you only use your hands with pen.

[hook-xf]

She has a sexy voice. I love the way she speaks. Girl got rhythm.

[rudycarv]

Is it ok to brake an exponent like when you broke 7 onto 5 + 2 ?
I stared to learn again Maths lol
BTW you've beautiful accent

[WhoBeSilly]

5 and 7 are definitely quite nearly. You have to pretension.