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[NecrosaroIII]

These formulas are very important to my job. But I don't understand why they don't work out to be the same.

Why

 

[diffusionx]

Because 1/.85 is not 1.15 and 1/1.15 is not .85.

Do you even number bro

 

[bender]

Zero difference.

 

[GymWolf]

you lost me at "x".

 

[Foamy]

What's a formula?

 

[triplestation]

infinity is not a number

it is a behavior

 

[TyphoonStruggle]

Same reason why x * 2.0 is not the same as x / 0.0

 

[triplestation]

set x to 0

HAHAHAHAHAHAHHHAHHAHAHAHAHAHA

 

[DESTROYA]

Im not doing your homework!

 

[poppabk]

1.15x=x/0.85
Multiply by 0.85
0.9975x=x
This can only be true for x =0
Basically 1.15 times 0.85 does not equal 1.

 

[FreedomOfSpeech]

Why would it be the same?

0.85 * 1.15 = 0,9775

 

[Atrus]

I’ve seen this issue when people try to calculate sales taxes.

In Canada we have a 5% GST so it’s pretty easy to calculate as follows: $100*1.05= $105.

What some people try to do instead is divide. Ex. $100/0.95= $105.26.

They don’t understand that the 5% multiplied is on $100 as a total where the 5% accounted for when dividing is not based on the $100 as a total.

 

[V2Tommy]

Why would it be the same?

0.85 * 1.15 = 0,9775

Exactly this. So easy to prove. You can't remove 10% and then add 10%. It won't be back at 100.
90% + 10% = ???

 

[bender]

Exactly this. So easy to prove. You can't remove 10% and then add 10%. It won't be back at 100.
90% + 10% = ???

I always give 110%.

 

[FreedomOfSpeech]

I noticed this problem in the dutch version of high school.

Some super smart math wizards (what we call the beta math, trig, calculus, algebra etc), did NOT understand percentages and how to work with them.

Always found it strange. I was so jealous of their math skills and then they utterly suck at this.

 

[Rentahamster]

Use algebra. If you think they're the same, then

(X * 1.15) = (X/0.85)

Multiply both sides by 0.85

X * 0.9775 = X

Which can't be right.

 

[Rentahamster]

set x to 0

HAHAHAHAHAHAHHHAHHAHAHAHAHAHA

The image of a shredded gym rat making this snarky math roast brings life to my inner thighs.

 

[IntentionalPun]

I'll explain it how I explained it to my peers who were bad at math:

HAHA RETARD YOU'LL NEVER GET A GOOD JOB!

 

[HoodWinked]

your original statement is:

x*1.15 = x/0.85
0.85 is an incorrect correlation that you came up with, so lets just make that z.

x*1.15=x/z
zx*1.15=x (multiply both sides by z)
1.15zx/(1.15x)=x/(1.15x) (divide both sides by 1.15*x)
z=1/1.15(cancel out)
z=1/1.15=0.86956521

so what you meant to say was:

x*1.15 = y/~.087

 

[Xplainin]

It just doesn't. Accept it and move on.
Its not worth the effort to understand it.

 

[PSYGN]

Im not doing your homework!

Indirect insults are the best.

 

[Ozzy Onya A2Z]

I always give 110%.

Your avatar is too good mate.

 

[Taxexemption]

Honestly, very few people ever explained anything to me logically about how numbers work and why they make sense. If I had time I'd love to start taking math classes over again, but it's pretty low on my priority list, and I probably already know more math than I need to for my job.


When I was twelve I was like "Dad, why does this thing with numbers work this way,"

"Son, I work on stuff with math that I don't know why it works. My boss doesn't know either. Hell, maybe only God knows. We just use the formulas the way we are supposed to and it works out. If you use the numbers and get the right answers long enough maybe it will start to make sense. Fake it till you make it."

 

[Tesseract]

Honestly, very few people ever explained anything to me logically about how numbers work and why they make sense. If I had time I'd love to start taking math classes over again, but it's pretty low on my priority list, and I probably already know more math than I need to for my job.


When I was twelve I was like "Dad, why does this thing with numbers work this way,"

"Son, I work on stuff with math that I don't know why it works. My boss doesn't know either. Hell, maybe only God knows. We just use the formulas the way we are supposed to and it works out. Fake it till you make it."

gotta learn the right way

i used practical man approaches like the feynman method

 

[infinitys_7th]

These are not equivalent expressions, as has been point out, but the cause of the confusion is the probably the notation.

• x * 1.15 is multiplying x by 1.15.
• x / 0.85 is dividing x by 0.85, or equivalently is x * (1/0.85). Division is really just shorthand for multiplying something by the reciprocal of something else - it is a special case of multiplication, just like subtraction is a special case of addition (e.g. adding negative numbers to another number).

1/0.85 is not equal to 1.15, so the expressions are not equivalent.

 

[SpartanN92]

You’re all a bunch of fucking nerds.

 

[Cunth]

is this how games are made

 

[West Texas CEO]

1.15/x=100/0.85
(1.15/x)*x=(100/0.85)*x
1.15=117.64705882353*x
1.15/117.64705882353=x
0.009775=x
x=0.009775

now we have:
0.85% of 1.15=0.009775

 

[Pumpkin Seeds]

You’re all a bunch of fucking nerds.

You say that but Backstreet Boys were always Tell Me Y


just like math teacher




So obviously its cool

 

[notseqi]

Everytime I have to calculate net/net/net prices I sit there like a complete fool and go through the whole thought process again.
/0.85 if you expect 15% being pulled as a rebate/bonus at a later point
x1.15 if you need to add 15% tax
I never cared why, that's just how the cookie crumbles.

 

[Cato]

These formulas are very important to my job. But I don't understand why they don't work out to be the same.

Why

1, you don't understand basic percentages
2, understanding basic percentages is very important for your job

I don't think you are in the right job right now.

 

[Spaceman292]

For the same reason that 3 does not equal 488.

 

[Rentahamster]