Dividing Thousands with Decimals?

Question

Whats the best way to divide large numbers?

Basically this is my question:

A new car costs £13500. The dealer gives a discount of £1282.50. What is the percentage discount?

Now the formula to work this out would be:
13500/1282.50 x 100 = %

But im stuck on dividing it. I cannot use a calc for this question. Would i multiply the both numbers again by 100 to remove the decimal, convert them to a fraction and simplfy them, and work on the division using a smaller number?

Thanks guys and girls.

PS. Im not asking how to do it, im asking whats the best way to divide the to upper numbers WITHOUT a calc. Im using paper and pencil and dividing the large numbers can become tedious.

Answer 1

1282.5/13500x100=9.5%

Answer 2

Firstly, you have the equation the wrong way around. You need 1282.50/13500 x 100 to give the percentage not 13500/1282.50

So when you multiply 1282.50 by 100 you get 128250, and you need to divide that by 13500. You can obviously cancel the final zero, to give 12825/1350. If you don't like long division, you can then divide both of those by 25 (or divide each one by five, and then five again, if you prefer) which will give 513/54.

Both of those numbers are obviously divisible by 9, since the digits add up to 9 in both cases, so cancel again and you get 57/6. You can do one more short division (both are divisible by 3) and then you're left with a simple division by 2 for your final answer.

Answer 3

You'd only need to multiply both by 10 to get rid of the decimal. (since .50 is equivalent to .5 ). If you want to go with the simplification route, that is fine, but I prefer to do it in one fell swoop. (Less time consuming that way). I guess it depends on your level of mathematic proficiency.

Answer 4

%iscount = 1282.50*100/13500% = 9.5%

Answer 5

simple take decimals out and multiply uper digit by 100

Answer 6

let there be x% of discount

then ,

(x/100 ) * 13500 = 1282.5

=> x= ( 1282.5 * 100 ) / 13500

x= 9.5 %


all the very best ... happy new year!!!