Percentage woes: total is 105, percentage is 5, then...

[mte]

Hi,

I need to work out the percentage amount of an amount that has already had the percentage added to it? For example, the total amount is 105 and the percentage is 5 then the amount calculated should be 5.

The percentage and total amount can vary, and can have up to two decimal places.

Any help greatly appreciated,

Michael

 

[jonboy]

Hmm Ill try to decipher what you said:

\(\displaystyle \frac{is}{of}=\frac{percent}{100}\)

Since you know the number, you are trying to solve for the "is".

\(\displaystyle \frac{x}{105}=\frac{5}{100}\)

Solve by cross products to calculate what 5 percent of 105 .

To get your total answer, add the \(\displaystyle x\) to your original number.

Can you take it from here :?:

 

[stapel]

I need to work out the percentage amount of an amount that has already had the percentage added to it? For example, the total amount is 105 and the percentage is 5 then the amount calculated should be 5.

It would help if you provided the exact text of the exercise. Thank you.

Eliz.

 

[jonboy]

I need to work out the percentage amount of an amount that has already had the percentage added to it? For example, the total amount is 105 and the percentage is 5 then the amount calculated should be 5.

It would help if you provided the exact text of the exercise. Thank you.

Eliz.

Oh *pheew* I thought I messed up by going to deep again. :wink: Yeah this question is discombobulating

 

[mte]

Thanks, i now think i have it. After calculating the value for x i then work out the percentage (x) of 105 giving me the amount i require.

i.e (in the example) x = 5.25. 5.25% of 105 = 5.

 

[Denis]

mte, WHAT are you doing :shock:

an amount + 5% of that amount = 105 : that's what your problem seems to state
x + .05x = 105
1.05x = 105
x = 105 / 1.05
x = 100

 

[mte]

Thank you. Makes sense now.