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Ch. 2 - Functions and Graphs
Blitzer - College Algebra 8th Edition
Blitzer8th EditionCollege AlgebraISBN: 9780136970514당신이 사용하는 게 아니라요?교과서 변경
3장, 문제 45

After a 30% price reduction, you purchase a 50″ 4K UHD TV for \$245. What was the television's price before the reduction?

검증된 단계별 안내
1
Let the original price of the television be represented by the variable \(P\).
Since the price was reduced by 30%, the sale price is 70% of the original price. This can be written as the equation: \(0.70 \times P = 245\).
To find the original price \(P\), divide both sides of the equation by 0.70: \(P = \frac{245}{0.70}\).
Simplify the right side of the equation to express \(P\) in terms of a numerical value (do not calculate the final number).
The result from the previous step will give you the original price of the television before the 30% reduction.

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
2m

주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

Percentage Decrease

A percentage decrease represents how much a quantity is reduced relative to its original amount, expressed as a percent. In this problem, a 30% price reduction means the new price is 70% of the original price, since 100% - 30% = 70%.
추천 영상:
02:44
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Original Price Calculation

To find the original price before a percentage decrease, divide the reduced price by the remaining percentage (expressed as a decimal). Here, dividing $245 by 0.70 gives the original price before the 30% reduction.
추천 영상:
5:59
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Decimal and Percentage Conversion

Percentages are often converted to decimals for calculations by dividing by 100. For example, 30% becomes 0.30, and 70% becomes 0.70. This conversion is essential for multiplying or dividing when solving percentage problems.
추천 영상:
4:47
The Number e