During a two-month period, the price of a barrel of oil increased by

Question

During a two-month period, the price of a barrel of oil increased by 15 percent by the end of the first month and then decreased by 10 percent by the end of the second month. If the price of oil was p dollars per barrel at the beginning of the two-month period, what was the price, in dollars per barrel, by the end of the period?

A. 1.5p
B. 1.05p
C. 1.035p
D. p
E. 0.95p

Show Answer

Official Answer

C

A. 1.5p
B. 1.05p
C. 1.035p
D. p
E. 0.95p

emockus · Answer

Set the price per barrel at $100. A 15% increase would set the barrel price at $115. The 10% decrease would set the barrel price at $103.50. P=100, going through the answer choices, answer choice "C" will equal the barrel price at the end of two months.

shaktirdas19 · Answer

(23/20)(9/10)p=1.035p

sashiim20 · Answer

During a two-month period, the price of a barrel of oil increased by 15 percent by the end of the first month and then decreased by 10 percent by the end of the second month. If the price of oil was p dollars per barrel at the beginning of the two-month period, what was the price, in dollars per barrel, by the end of the period?

Price of the barrel at the beginning of 2 month period = p
Price of barrel increased by 15 % by end of first month = 115% of p = $\frac{115}{100}$ x p = 1.15p
Price of barrel decreased by 10% by end of second month = 90% of 1.15p = $\frac{90}{100}$ x 1.15p = .9 x 1.15p = 1.035p
Therefore price of barrel at the end of period = 1.035p ...... Answer C ....

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matthewsmith_89 · Answer

p x 1.15 x 0.9 = 1.035p
Which is answer C

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During a two-month period, the price of a barrel of oil increased by

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During a two-month period, the price of a barrel of oil increased by

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