$x-12\%=100$, find $x$

Question

I need to pay someone after deducting $12\%$ commission. I want to pay him round amount of $10,000$ What is the formula to establish the $112\%$ figure so that once I have deducted my comm I will be left with $10,00$. I know the answer is not $11200$ because $11200 - 12\% = 9856$.

Please help me with a formula that will calculate $x - 12\%= 10,000$ or $x - 12\% = 7000$ or $x-12\% = 5000$.

Thanks so much, Maurice

Possible duplicate of How do I start from a 10% discount and find the original price? — , Nov 28 '15 at 23:22

score 1 · Answer 1 · answered Nov 28 '15 at 15:28

1

One may observe that, in general, $$ x - a\%\:x=b $$ is just $$ \left(1-\frac{a}{100} \right)\times x=b $$ giving, if $a \neq 100$,

$$ x=\frac{b}{\left(1-a/100\right)} $$

answered Nov 28 '15 at 15:28

Olivier Oloa

120,989

But in this case it's $x-a%=b$, not $x-a%x=b$. – user236182 Nov 28 '15 at 15:36
2

@user236182: Errr... "12% commission" means "12% times the total".. so your formula "$x-a%$" is wrong and Olivier's correctly represents what you want. – user21820 Nov 28 '15 at 15:38
3

I think the OP means $12%x$ when writing $12%$. – Olivier Oloa Nov 28 '15 at 15:38
I only read what the title said, my bad. The answer to the title question would be $x=\frac{100b+a}{100}$. – user236182 Nov 28 '15 at 15:41
$x-12%$ is a colloquial/clumsy way to express $x$ less twelve percent of it. Deducting $0.12$ would not be expressed as $-12%$. – Nov 28 '15 at 15:59

score 1 · Answer 2 · 2015-11-28T16:28:33.937

1

$88\%$ of $x$ is $10000$, then $x=\dfrac{10000}{88\%}=10000\cdot\dfrac{100}{88}=11363.63$.

Check: $88\%$ of $11363.63$ is $9999.99$.

edited Nov 28 '15 at 16:28

answered Nov 28 '15 at 15:55

Archis Welankar · Answer 3 · 2015-11-28T15:49:58.277

-1

see its quite simple sorry for misinterpreting first time. so here we assume total amount to be $x$ thus you want $12\%$ commision of $x$ and extra $10K$. so our equation becomes $\frac{12x}{100}+10000=x$ thus on solving you get $x=11363.63..$ now i hope i have interpreted your question correctly.

edited Nov 28 '15 at 15:49

answered Nov 28 '15 at 15:41

Archis Welankar

15,910

$x-12\%=100$, find $x$

3 Answers3