math help...again!!?

Question

ok. Explain how you can find out how much a 15% tip would be without a calculator or a scrap paper.

plz gimme real answers. no insults. im not in the mood. thanks!!

plz answer this quickly!! thanks!

Answer 1

Here's a way to do it, using the example of a $20 restaurant bill. To determine 10% of any amount, move the decimal two places to the left. This would make 10% of $20, $2.00. Now, you want to determine 5%, which would be half of 10% (half of $2), making 5% = $1.00. Now, add the 10% and 5% together: $2 + $1 = $3.00.

I'm afraid this sounds more complicated than it is, but once you get used to doing math and percentages in your head, it's really not that hard.

Answer 2

Method ONE:

Say I get a bill for 5.63

Calculate 10% first: Move the decimal over one place so the number gets smaller-> .563, or about 60 cents.

To get your extra 5%, Then divide that by two --> 60/2 = 30 cents

Add you first number to your second -->60+30= 90 cents

(Does this make sense? You have 10% + 5% which equals 15%)

Method TWO

Now, I used to be a waitress, and if I did even a fair job, I hoped for 20%. Now I usually give 20%, because I am nice AND because it is easier to calculate!!
You want to do 10% + 10% = 20%.

So for your bill of $16.38, your 10% is $1.63, and then just add another $1.63 to get ... I don't know, just do $1.50 and $1.50 and get $3. A little more for great service, a little less for lazy work!

Method THREE:
Memorize a table. At home, figure out how much 15% is for certain bill cost. Just memorize it and give about that much. Believe me, the waitress will only do the math if it seems really low or really high!

For instance for ! Pay this
$5 ! .75
$10 ! 1.50
$15 ! 2.25
$20 ! 3
$25 ! 3.75
$30 ! 4.50

See the pattern? 75 cents for every $5.

Conclusion:
Different people use different methods depending on how their brain works. You can do it too! And when in doubt OVER-TIP!!!

Answer 3

Easy.

10% is just moving a decimal place, so let's say the bill is 13.56.
Moving the decimal, would make it 1.356, but that is only 10%.
Half of that is the other 5%.
So half of a buck 35 is 65 cents or so. 1.356/2 = 0.678 or 68 cents to be more precice.
Then just add 1.35 and 65 to get 2.00.

Answer 4

Well - you'd need to know the total to calculate 15% of it.

The quickest way is to divide the total by 10
and that's 10%

Then you need to divide that number by 2
and that's 5%

Then you need to add the two numbers together to make 15%

You normally can do that in your head.

Answer 5

The easiest way to do this is to look at the bill and for every $10.00 add $1.50. So if the meal cost $50.00...thats 5 $10.00...so 1.50 5 times...which is 7.50. And depending on the state and alcohol you can sometimes just double the tax on the bill.

Answer 6

the easiest way that comes to mind is think in 10 for instance 10% of 5.60 is .56 cents so for 15% would be .56 + half of .56 is .28 so it would be .84

Answer 7

Multiply by 15, then divide by 100. Simple as that. This will give you the tip only, not price + tip.

Answer 8

finding 10% is easy, just move the decimal over....exaple 10% of 10 is 1. so then find the ten % and cut it in half... so its a half of one is .5. ad it up ad 15% of 10 is 1.5