The figure shows the distribution of retail electricity rates in 2007

I can explain Question 1.
But my average answer question 2 is nearby 71%
That is definitely not near to 95%.

Posted from my mobile device

can someone please explain the second question? what does it mean?
And also post the OA for the same

Pls explain the second part, did not really get the stem and solution?

Certainly! Please go ahead and ask any questions or provide more details related to the distribution of retail electricity rates in 2007 for the five states in the U.S. in cents per kilowatt-hour. I'll do my best to assist you based on the information you provide.

Did not understand both the parts please explain

Posted from my mobile device

What do you suggest if I got this right but it took me 5.20 mins ? Should I be happy with that?

Not at all! Your time for any single DI question must not go beyond 03:30. If you think any particular question may take more than that; it is better to guess that question within 30 seconds and move on.

Official Explanation:

Note that the lowest cost per kilowatt hour listed in the figure is 6-8 cents, so therefore any unaccounted for percentage for any of the listed states must be at a cost of < 6 cents per kilowatt hour, since the questions states that the highest cost range per kilowatt hour is listed for each of the five states.

According to the figure, approximately 100% of the cost range is accounted for each by the bars representing each of Massachusetts, Pennsylvania, Colorado, and Mississippi. However, the only bars for Washington listed are approximately 59% at 6-8 cents per kilowatt hour and approximately 35% at 8-10 cents per kilowatt hour, leaving approximately 6% of the distribution unaccounted for, which must be at a cost less than 6 cents per kilowatt hour. The correct answer is E


According to the conditions of the problem, approximately 3% of Massachusetts energy customers would pay 12 cents per kilowatt hour and approximately 97% would pay more than the 13.31 cents per kilowatt hour nationwide average. Meanwhile, approximately 31% of Pennsylvania energy customers would pay 14 cents per kilowatt hour and approximately 69% would pay less than the 13.31 cents per kilowatt hour nationwide average.

Now, use the percent change formula to calculate the difference in likelihood of selecting a Massachusetts energy customer paying less than the nationwide average against a Pennsylvania customer paying less than the nationwide average.
Use the calculator to determine that (69 - 3) / 69 = 95.65%. The correct answer is D

­for the second part, why would it be % change

­The whole language of the question and arguement is at an issue here. 

­A. If the highest cost range per kilowatt hour is listed for each of the five states included in the figure, then the state with the greatest percentage of customers spending less than six cents per kilowatt hour is [Washington].

Meanwhile, the graph already displays the highest score range
=> the remaining of each state's customers not shown in the graphs are those spending < 6 cents/kwh

The graph show % of each state's customers as below

• C: \(7 + 80 + 13 = \approx{100}\) 
• Mis: \(16 + 52 + 32 = \approx{100}\) 
• W: \(60 + 35 = 95\)   
• P: \(38 + 32 + 30 = \approx{100}\)
• Ma: \(2 + 10 + 50 + 40 \approx{100}\)

=> Washington

B. If the average U.S. residential energy customer pays 13.31 cents per kilowatt hour, and every consumer paid the maximum amount per kilowatt hour for each of the ranges listed in the figure, then a randomly selected energy consumer from Massachusetts would be approximately [97%] less likely to pay less than the average than is would be a randomly selected energy consumer from Pennsylvania.

13.31 is in range 12-14

Ma: only 2% in the range below 12-14 (i.e range 10-12)
P: 70% in the ranges below 12-14 (i.e 38% in range 8-10 and 32% in range 10-12)

Likelihood of pick Mas < Avg: 2%
Likelihood of pick P < Avg: 70%

% difference: \(\frac{(70-2)}{70}=\approx{97%}\)­

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