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gdogthegirl
Help please!? The sales tax on a new car varies directly to(or is directly proportional) the price of the car. If $1,800 in sales tax is paid for a $25,000 car. what is the purchase price of a car worth $1,600 in sales tax? Im totally lost when it comes to variations :(
could you show the steps too?
It's a question in proportions. 1800 is to 25000 as 1600 is to x. Are you with me so far?
but im not supposed to use proportions
its for variations like this is a direct variation
"varies directly" is the same as proportions. You will use an equation like a/b = c/x.
1800 = a. 25000 = b. 1600 = c. Just get x
25000/1800 = x/1600 25000/1800 = 13.89 1800 x 13.89 = 25 1600 x 13.89 = x
the equation they gave to use to use was y=kx ^{n} \]
What is your value for k?
that what i dont know