Yeah; I got it right again, pretty good for a 70 year old retired physician who started doing math again after 50+ years not doing it! I got interested in math as I have been substitute teaching and todays students need help learning their Arithmetic. So I lucked out and found this master teacher! Thanks! -20/-4 = 5; it’s fun to get the right answer.

Typographical point: the symbol between the 5 and the 8 is NOT the symbol for the operation of multiplicationl. It's trying to be, but it's not...

@matikramer9648

5 ай бұрын

It is old simbol of multiplication. It was such in 1960 - 1985 in eastern Europe

[40:(-2)]/(2-6)= (-20/-4)=5

John my dear fellow, brilliant video but you're getting a bit quiet! Maybe you could turn the record level up a little? Thank you and God bless.

@mariee.5912

5 ай бұрын

I can hear ok.

64 this year, I did the problem in my head and am happy with my answer. Thank you for the brain exercises.

@achimhuttermann6885

5 ай бұрын

So did i (56years old).

5 x 8 / -2 divided by 2 + -6 This is more about getting the plus and minus right 40 / -2 divided by 2 + -6 plus divided by minus = minus -20 divided by 2 + -6 plus minus = minus -20 divided by -4 = 5 minus divided by minus = plus

@stevenpollard5171

5 ай бұрын

You are saying plus and minus when you should be saying positive and negative. They are not the same!

@user-gx1rk8yw6l

5 ай бұрын

@@stevenpollard5171 Totally agreed. But the mistake is too easy to make. *At least 2* symbols exist for the division operation. *Ditto 2* symbols for the multiplication operation. PLUS, we have *4* sets of symbol-pairs for grouping. (Plus &c, &c.) Yet the *1 available* positive sign is identical to the symbol for addition? And the *1 available* negative sign is identical to the symbol for subtraction? Is the collective population of the mathematical world NUTS??? And while I am ranting anyway, this: Since the absence of an explicit sign is assumed to mean positive, an absolute value can NOT be stated without the "||" sign/operator. (And which is it, sign or symbol or operator or ...?) Also, the "=" in "X=Y" meaning both "X is equal to Y" AND "give X the value of Y"... (For the latter even Basic originally had "LET X = Y", & Algol still has X := Y".) Not to mention the absolute idiocy of "multiplication by juxtaposition"...

I have an RPN calculator. It gives the correct answer. If you use an algebraic calculator, remember to use parenthesis around the numerator and denominator to get the correct answer. On RPN the keystrokes are 5 enter 8 X 2 CHS / 2 enter 6 CHS + / On Algebraic the keystrokes are ( 5 X 8 / 2 CHS ) / ( 2 + 6 CHS ) =

There was a time I was afraid of math but I've pushed myself to learn more and more. I, too, did this problem in my head and was pleased to get the answer right. BTW, I love this math channel.

@stevejones9905

5 ай бұрын

That is a great feeling.

@deloresford5681

5 ай бұрын

Thank you 👍🏾

How about: (step1) 8/-2 =-4 (step 2) 2+(-6)=-4 (step 3) 5x(-4) divided by (-4) the (-4)'s cancel just leaving 5.

At the title card, still a little rusty as I delve back into a formal algebra class, gettng c) 5 as my answer

Yeah, I also got it right again, also decent for a 70(plus!) year old computer professional who blushes to admit he was a math major many years ago. Sure glad we've got this review of material I've long forgotten.

Is factorial considered a bracket?

I did it in my head. Math 1960

super simple top is just left to right in this case. so 5 times 8 is 40 then divided by negative 2 is -20 Bottom is just 2 - 6 which is -4. A negative times a negative is a positive also a negative divided by a negative is a positive. So final answer is c:) 5

Thank you

@tabletclass Thank you for the *correct* explanation of the OoO! You know that PEMA would have been a better mnemonic, right? (For those who do NOT see this: a division is an inverted multiplication, & a subtraction is the addition of a negative.)

I enjoy these exercises to keep the 50 yr old brain sharp.

👁just came across your channel and immediately subscribed…..❤️❤️❤️👍🏾

I don’t get why so many say this is too easy. It’s supposed to be. It’s a refresher.

5

Mixing nomenclatures is not permitted.

C) 5

So so tired of the negative attittude of “many will get this wrong”

Yall tripping. I understand the multiplication symbol but it’s obvious in this problem that it’s being used as a multiplication symbol.

I remember most of those years

got it 5 thanks for an easy one

-20÷-4=5

I did mentally. But my math is rusty 😆 not because of age John, but because I don't practice.

-5.

I got the right answer. I am 77

@kjellg6532

5 ай бұрын

Me too, and I didnt need 15 minutes.

C)

Teacher my question to you is. "What is the largest number known to man"?

20/3 ??

The numerator needs parentheses, to remove anbiguity. División is not associative! If You Say that You must procede left to right or in a given order, that is a programming language, but not precisely mathematics

@user-gx1rk8yw6l

5 ай бұрын

*Not so* WHEN WRITTEN AS IT IS ON THAT GREENBOARD. But to write it correctly in the form of a SENTENCE, like on the line here-below: [ 5 * 8 / (-2) ] / [ 2 + (-6) ] then this problem MUST use grouping on BOTH sides of the division symbol (the symbol that is on the greenboard represented by a long horizontal line). 1 note: the "x" in "5 x 8" is ambiguous: is it the letter or the multiplication-symbol? If it is meant as multiplication-symbol, then using the "*" is NOT ambiguous. If it is meant as the LETTER, then the problem has suddenly become REALLY INTERESTING, namely a statement with an unknown that is NOT an equation...

@GaryBricaultLive

5 ай бұрын

Since the numerator is a multiplication followed by division it does not matter which is performed first. There is no ambiguity. Ex: (5 * 8) / -2 = -20 and 5 * (8 / -2) = -20 . The denominator is defined by the line and forces it to be evaluated uniquely. @@user-gx1rk8yw6l

@user-gx1rk8yw6l

5 ай бұрын

@@GaryBricaultLive The ambiguity is in reference to whether the "x" is a letter or a multiplication-symbol. Whichever one assumes makes a big difference to the problem itself. Just-because 1 assumption seems offhand to make more sense than the other is not a valid reason for that choice. That "x" might be INTENDED as a letter, in which case the NUMERATOR is: 8x5/(-2) = (8 * x * 5) / (-2) = (-20)*x

I’m older than 64, did it in my head quickly, and got it right

Answer = 5

How 5x is divided by natural number 😊

Answer is 5

"Work these problems simultaneously, one step at a time." Referring to the problem being a fraction. Very confusing.

B? -5???? No soup for me! My mistake: 4 should've been -4... did in head. Probably would've made same mistake.

@stevejones9905

5 ай бұрын

I'll share my soup with you.

@mariee.5912

5 ай бұрын

When you divide neg by neg =positive.

These are too easy. In the answers, he needs a 5th choice: e) None of the above, just to spice it up a little. 😊

-5 Oops.

Yes! 💪😂😍

-20 / -4 = 5 too easy!

Many will not understand because you have used the incorrect font for the multiplication symbol.

@crinolynneendymion8755

5 ай бұрын

That is not a multiplication symbol; it's the letter "x". It is not the "many" who misunderand; it is the one who can't write an expression properly to go back to school and learn how to be rigorous.

@user-gx1rk8yw6l

5 ай бұрын

@@crinolynneendymion8755 I am beginning to wonder whether the video's author is *deliberately* setting such traps. Because they sure separate the "THINKING-CAP-ON" responders from the "by-rote-plodding" commenters... It would also give more solidity to his statement of "decades of teaching math"--ie as a WARNING to THINK, rather than as a boast. (That feeling is NOT new; this is simply the 1st time that I *air* that feeling.)

@cwphat1

5 ай бұрын

ooooooooooooo... ok😂😂😂😂

Forgot a negative divided by a negative is a positive.

Aunt sally . Oh boy

EZ!

who cares

B

Thank you

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@mpall88

5 ай бұрын

Of course the answer is 5. The fact that it took more than 14 minutes to explain that answer is rediculous. Thumbs down.

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