converting intofraction to percentage in a quicker way?

Question

many a times i take lot of time to convert a fraction into percentage .

i need a quicker way to get it . the answer need not to be exact but approximately .

How do i convert this fraction into percentage quickly

1670.3/2098.3

please tell me the steps so that i can apply the same rule for other fractions.

can we apply the same rule if i had

167.2/(2098.3) ?


please post your valuable comments.

thank you

hey , i asked a quicker way .

i know the usual way , how to do it ...simply by dividing and multiply by 100.

I am asking a quicker way to avoid a bad long division ,.... you know this kills time.

need some other alternative .

Answer 1

assuming you don't have a calculator available (which is about the easiest way - divide, move the decimal two places to the right and stick a % sign after it...)

if you don't care about the accuracy of your answer, you could try this.....

1) round as needed.

2) figure out what 10% of the denominator is by moving the decimal point 1 place to the left.

3) figure out what 1% is

4) divide number by two to get 50%

etc...



for the first example,

1670.3 / 2098.3 is approximately = 1650 / 2100 = 16.5/21

and 75% of 21 = 1/2 of 21 + 1/2 that again.... = 10.5+ 5.25 = 15.75

since 10% of 21 = 2.1

1/2 of 2.1 = 5% of 21 = 1

75% = 15.5/21
80% = 16.5
85% = 17.6

so your answer is about 80%

for the second problem

10% of 2098.3 = 209.83
1% = 20.983

209.83 - 167.2 = 42.63 = approximately 2 x 1%

so your answer is about 10% - 2% = 8%

Answer 2

If you don't want an exact answer, multiply the numerator by 100 and round both the numerator and denominator. In this case
167000/2000 = 83.5%
error is -3.897%
167000/2100 ≈ 79.5%
error is 0.0787%
16720/2000 = 8.36%
16720/2100 ≈ 7.96%
actual ≈ 7.968355%

and, no, in general there just isn't any faster way unless you can factor the numbers and cancel common factors.

Answer 3

multiply it by 100 after doing the division, that's all

The % sign means per hundred, or divided by 100.
So you keep it at it's original value when you multiply it by the 100

Oh, you meant not using a calculator? Hardly necessary to know how to do that in my opinion....

Answer 4

Unfortunately, there is no alternative available. Try getting quicker at doing the division.

Answer 5

Just perform long division... that is... divide the numerator by the denominator... stop when you have reached a level of precision that you are happy with.