The Heading of the chart gives "AVERAGE COSTS OF OPERATING SUBCOMPACT, COMPACT, AND MIDSIZE CARS IN THE UNITED STATES"

So what we have in the graph are already average costs of operating cars in various segments. What we want to find is the difference between these values for compact and sub compact cars in various years.

1982 - The figure for subcompact is about .34 and for compact is about .45 - The difference is .11
1983 - The figure for subcompact is about .34 and for compact is about .44 - The difference is .10
1984 - The figure for subcompact is about .36 and for compact is about .48 - The difference is .12
1985 - The figure for subcompact is about .40 and for compact is about .47 - The difference is .07
1986 - The figure for subcompact is about .40 and for compact is about .48 - The difference is .08

All these values lie in the range (D)
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Average cost per mile for a compact car = (0.45+0.45+0.45+0.48+0.49)/5 = 0.48

Average cost per mile for a sub-compact car = (0.33+0.33+0.36+0.4+0.4)/5 = 0.364

Difference = 0.48-0.364 = 0.116

This lies in the range given in D, which is thus the answer

Here in this questions we need to look into the bar chart for difference in blank white bar and black bar values for every year ... and then get the lowest and highest difference values.... and check in answer option which one satisfy.
IMO D

We see that for compact cars, the average costs are:

0.45, 0.44, 0.48, 0.48, 0.49

We see that for subcompact cars, the corresponding average costs are:

0.33, 0.33, 0.36, 0.40, 0.40

Thus, the differences between the average costs of compact cars and subcompact cars are:

0.12, 0.11, 0.12, 0.08, 0.09

These differences are between the values of 0.06 and 0.12.

Answer: D
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hey amanvermagmat

here is my solution I dont get why I am getting wrong answer

Average cost per mile for a compact car 0,45 +0,44+ 0,48+ 0,47 +0,49/ 5 = 0.283 approx 280

Aver1age cost per mile for a sub-compact car 0.33+0.33+36+40+40/5 = 0.182

0.280-0.182 = 0.41

how on earth you calculate differently ? pls explain i really dont get

thanks!:)

Estimate:

1982: .45 - .32 = .13
1983: .45 - .33 = .12
1984: .48 - .37 = .11
1985: .47 - .40 = .07
1986: .49 - .40 = .09

The min I get is .07. The max I get is .13. This leaves on choices C and D on the table. The min of C is .09 which is much higher than .07 so through POE, I would choose D.

Keep in mind that you only have 2 minutes to solve a question. If this approach works for you, then great, but I would recommend estimating the averages for each year to solve this problem. It's a 40 second solution at best.

Anyhow, (0,45 +0,44+ 0,48+ 0,47 +0,49)/ 5 = 0.46 approximately, not .283. Same issue applies to the second calc you listed, your totals are wrong.

Instead if adding up all the subcompact and compact cost per miles , you can take the difference individually (as in Solns posted above)as the Q stem asks for "For each of the year"?
It could save you time and calculation mistakes IMO.

Interesting question type.

To me, it looks closer to what I would expect from an IR question in today's GMAT format.
Is there still a chance to encounter a question like this in the Quant section 2019?
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Anyone else feel like this is a terrible question? The approach is pretty obvious, so the only thing that can trip you up is making slightly inaccurate guesses based on a bar graph with too little scale detail.