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dlencz
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Here's the question:
The price of car A increased by percent over the same time period that the price of car B decreased by percent. The reduced price of car B was what percent of the original price of car A?
The increased price of car A is equal to the original price of car B.
The increase in price of car A was of the decrease in the price of car B.
And here is Knewton's explanation:
(If x= car A and y= car B)
Statement 1 tells us that the increased price of car A (1.2x), is equal to the original price of car B, y:1.2x = y. Since this gives us a relationship between x and y, we can answer the question. Statement 1 alone is sufficient. The answer is A or D.
Statement 2 tells us that the increase in price of car A (0.2x), is equal to 5/6 the decrease in price of car B, 0.2y:0.2x = 5/6 * 0.2y . This also gives us a relationship between x and y. Statement 2 alone is sufficient to answer the question.
I'm getting lost on the ratios. For example, if the increased price of car A is equal to the original price of car B isn't that just 1.2x = y? Why is it y:1.2x = y?
Just thinking about it at a high level it's fairly obvious there's enough information from both to solve but I'd like to understand the math behind it.
Thanks for the help.
The price of car A increased by percent over the same time period that the price of car B decreased by percent. The reduced price of car B was what percent of the original price of car A?
The increased price of car A is equal to the original price of car B.
The increase in price of car A was of the decrease in the price of car B.
And here is Knewton's explanation:
(If x= car A and y= car B)
Statement 1 tells us that the increased price of car A (1.2x), is equal to the original price of car B, y:1.2x = y. Since this gives us a relationship between x and y, we can answer the question. Statement 1 alone is sufficient. The answer is A or D.
Statement 2 tells us that the increase in price of car A (0.2x), is equal to 5/6 the decrease in price of car B, 0.2y:0.2x = 5/6 * 0.2y . This also gives us a relationship between x and y. Statement 2 alone is sufficient to answer the question.
I'm getting lost on the ratios. For example, if the increased price of car A is equal to the original price of car B isn't that just 1.2x = y? Why is it y:1.2x = y?
Just thinking about it at a high level it's fairly obvious there's enough information from both to solve but I'd like to understand the math behind it.
Thanks for the help.
