Holy crap! I'm so confused over something so simple. Can you help?

Question

If oil consumption increased from 10 units to 20 units over a period of time, was that a 200% increase or a 11.00% increase?

10 x 1.15 equals an increase of 15 percent, right? Then,
10 x 1.99 equals an increase of 99%, right? So, 10 x 2 equals an increase of 100%, right?

But if I divide 20 by 10 then that equals 2 and when I multiple by 100% I get 200%! Like I said, this is confusing me and it shouldn't. What have I forgotten?

You guys rock! Thank you! My son asked me for help and I had a brain fart. I've just been doing the math for so many decades without thinking about it that the simple became complex. We get it! Thanks!

Answer 1

The first part is an increase of 100%

You started by using 10 units, so 10units represents 100%.

now you add another 10 units so you use 100 + 100 % of original amount

so you use 200% of original amount. You started by using 100% so you subtract 100% from 200% to get 100% increase

This example following makes the working clearer.

you start using 10 units.

The fist quantity in thes sums always represents 100%

Suppose you increase your consumption to 30 units

The increase in consumtion = 30 - 10 units

=20 units

the orignal consumption = 10 units reps 100%

so increase, 20 units = 100 x 20/10%

=200%

Answer 2

It is a 100% increase, but 200% of 10.

The increase means how much was increased compared to the original value. The original value was doubled, so the amount of increase was the original value - 100% of it.

However, 20 in terms of 10 is 200% of 10. It's a very important distinction, and I'm glad that you were thinking about it. The increase is the difference between the values divided by the original value (then multiply it by 100 to get the percent form) .

Example:

What is the percent increase from 7 to 10?

10-7=3
3/7 is the decimal expression of the percent increase, 300/7 is the percent form. 7*(1+3/7) = 10

Answer 3

Percentage Increase = change/original * 100%
= (200 - 100)/100 * 100%
= 100%
ie there is a 100% increase in the consumption

It depends on what you are comparing the increase to. When you divide the final by the original you are not getting the INCREASE, you are comparing the final to the original

If the final is 200% of the original then the original has INCREASED by 100% (The emphasis is on the words not a yell LOL)

Answer 4

It's clear you have your numbers mixed up.

Let 10 units be equal to 100%, then:

10u = 100%. (x2)
20u = 200%.
Increase in percentage = New % value - Old % value.
Increase in percentage = 200% - 100%
Increase in percentage = 100%

Think about it, if the units double, then the percentage double, and the increase will be half the new percentage value.


It's assumed now that you are starting off again with ten units for you next question.
10u = 100% (÷ 10)
1u = 10%

10u x 1∙15 = 11.5u
11.5u x 10% = 115%
Increase in percentage = New % value - Old % value.
Increase in percentage = 115%% - 100%
Increase in percentage = 15%

10u x 1∙99 = 19∙9u
19∙9u x 10% = 199%.
Increase in percentage = New % value - Old % value.
Increase in percentage = 199% - 100%
Increase in percentage = 99%

10u x 2 = 20u
20u x 10% = 200%.
Increase in percentage = New % value - Old % value.
Increase in percentage = 200% - 100%
Increase in percentage = 100%

Yes: 20/10 = 2
and: 2u x 100% = 200%.
But remember, 20u is double what you started off with, and so you get 200%. This is an increase of 100% compared to what you started off with (10u).

Answer 5

10 x 1.15 is not an increase of 15 percent.
that is an increase of 115 percent.

.15 is 15 percent.

if you want to find the increase of 15%. it would be 10 x .15 = 1.5 + 10 = (11.5)
and if you want to find 15% off. it would be 10 x .15 = 1.5
10 - 1.5 = (8.5)

from 10 units to 20 units is a 100% increase.

if your still having problems. contact me through my e-mail. i dont mind helping.

Answer 6

sorry i cant help you i hope you find the answer-ash