Mathy, mathy, mathy math

[angelchicken]

Hello my mathematically minded friends! I have a question for you!

Say you buy film from a distributer. The book price is $43.40 and the discount price you get is $38.63.

How do you calculate the discount? What is the formula you use?

When I worked with diamonds, we would calculate the discount using :

(38.63- 43.40)/43.40= X (-11%)

Is it the same thing? I have a bunch of discounts I need to do (I can use excel and just copy the formula down) and I am not completely sure how to do it. If you could offer assistance I would really appreciate it.

Thank you so, so much!

Comments

[jaybitvees.livejournal.com]

Writing it as a formula: b(1 - r) = d

where
b = Book Price
r = Rate of Discount
d = Discount Price

Step 1--> 43.40(1 - r) = 38.63
Step 2--> -43.40r = 38.63 - 43.40
Step 3--> r = (38.63 - 43.40)/-43.40
Step 4--> r = 0.1099
Rate of Discount = 10.99%

Buying the item at $38.63 is approximately 11% discount from the $43.40 book price.

[jaybitvees.livejournal.com]

Rewriting the formula to calculate for r:

r = 1 - (d/b)

[truecrystal.livejournal.com]

That'll work or you could use

100 -(discounted price/original price).

Using your example:

100 - (38.63/43.40)= 100 - .89 = .11 or 11% discount.

[truecrystal.livejournal.com]

Ugh. Not 100. Just 1. Or what the guy above said.

Stupid slow computer.

simple

[(Anonymous)]

it's a very simple equation:
43,40-38,63=4,77 (discaunt in $)
43,40: 4,77=100:x
x= 4,77x100/43,40
x=10,99

saturnine

[ghoulchick.livejournal.com]

Wow. I look at that and wonder how I ever passed calculus.