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kbuehner
Dec 5, 2008, 09:32 AM
I need to be able to calculate percentages with out a calculator and not just the simple ones such as 10% 20% 30% and so on.
e.g.. 23,546 of 53,487 what is the percentage with out a calculator.:eek:

ebaines
Dec 5, 2008, 09:57 AM
Obviously to get the exact answer you either have to be very good at doing math in your head or use a calculator. However, if an approximate answer is good enough, then you can go through a thought process like this:

23,546 is around half of 53,487. So if you round 53,487 down to 50,000 (i.e. by taking off 3,487) you can reduce the 23,456 by about half of 3,487, or by about 1750. So the 23,456 gets reduced to something around 21,700. So the ratio is now 21700/50000. Multiply by 2 so that the denominator is in nice round units of 10:

43,400/100,000

Or 43.4%.

The actual answer (with calculator) is 44.02%, so this is a pretty good approximation.

Doing this in your head may take some practice, but it's a great skill to learn. Basically think through math operations that turns the denominator into round numbers and go from there.

ScottGem
Dec 5, 2008, 10:03 AM
Excuse me, but where you not taught long division in school?

Percentages are simply a long division equation.

kbuehner
Dec 5, 2008, 11:55 AM
Can we do one more please
22,654 of 88,465 thanks:)

kbuehner
Dec 5, 2008, 12:27 PM
How can I figure out percentages with out a calculator.
e.g. 24,567 of 88,122
Had one great answer from previous question but would like one more.
:eek:

galactus
Dec 5, 2008, 01:00 PM
Think of percentages as counting pennies. A percent is based on 100.

There are 100 pennies in a dollar, so 1 penny would be 1/100=.01=1%

23 pennies would be 23/100=.23=23%

and so on.

For yours, just divide;

\frac{24567}{88122}=\frac{431}{1546}=.2787839...

Multiply .2787839 by 100 and get about 27.9% with rounding.

Assuming that is what you mean.

ScottGem
Dec 5, 2008, 02:28 PM
Please do NOT start a new thread for follow-up. Use the Answer This Question option. I've merged the three threads for you.

I have to ask, if you are sitting at a computer, why can't you do these yourself?

Unknown008
Dec 6, 2008, 01:30 AM
Can we do one more please
22,654 of 88,465 thanks

Round up if you don't need exact percentages. You can change 22,654 to 22,000 and 88,465 to 88,000. Then, 22,000/88,000 gives 1/4 which is 25%