Logical Reasoning

PT16 · S2 · Q9 From 1973 to 1989 total energy

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From 1973 to 1989 total energy use in this country increased less than 10 percent.

Facts

math-y comparison + pivot (however)

Total energy use went up by less than 10%. but Use of electrical energy went up by more than 50%.

The GNP also went up by more than 50%.

Evaluate

This stimulus reads Math-y Paradox all the way.

How can electrical energy use go up more than 50%, but overall energy use goes up less than 10%?

But there are a couple ways to resolve that paradox: 1) It could be that electrical energy is a tiny proportion of the nation's overall portfolio.

If 95% of energy came from coal and only 5% of energy came from electric, then when electric energy increases by more than 50%, it still doesn't change the overall energy usage that much.

Increasing 5 by 50% gets you to 7.5.

So instead of 95 (coal) and 5 (electric) = 100 (overall) now we have 95 (coal) and 7.5 (electric) = 102.5 (overall)

The overall went up by less than 10%.

2) It could be that other forms of energy got used less. Maybe 50% of energy came from coal and 50% from electric, but now it's more like 25% comes from coal and 75% from electric.

Since there are multiple ways to resolve the paradox, neither must be true. The fact about GNP would be even more vulnerable to multiple explanations.

Goal

Since we can't narrow down to one definite cause for these percentages, the correct answer is more likely to just test some math-y comparison we can derive?

9.

If the statements above are true, then which one of the following must also be true?

  1. Most of the energy used

    Too Strong

    There's no way we could prove that more than 50% is now electrical. In fact, this would make the math-y paradox more confusing. One way to explain the facts would be to say that electrical energy comprises a very small proportion of the nation's energy. This answer is actually more at odds with the facts than supported by it.

    2% picked this

  2. From 1973 to 1989 there

    Unsupported

    This is one possible way to explain how electric could go up > 50% while overall energy goes up < 10%. But this explanation doesn't have to be true. If electrical energy were a very small share of the overall energy usage, then all other types of energy could continue to be used just as much, and that would also explain the math-y paradox.

    17% picked this

  3. Correct

    From 1973 to 1989 there

    Why this is right

    Total energy use grew less than 10%, but electrical energy use grew more than 50%. Whenever a component grows faster than the whole is growing, that component's share of the whole must increase. If the total revenue of fast food restaurants went up 5% in 2025, but Wendy's revenue went up 7%, then they are gaining market share. If Chick-Fil-A went up only by 3%, then they are losing market share. If every restaurant were holding their market share steady, then all the restaurants would increase by 5%. In each of our two possible explanation scenarios, the proportion of energy that was electrical went up. We had other things holding steady while electrical grew (which balanced out to be a modest < 10% increase overall). Or we had electrical growing while other things shrunk. So in either case, the importance of electrical is growing. If all energy forms matched electrical, by increasing by more than 50%, then overall usage would increase by more than 50%. The fact that overall is less than 10% means that electrical growth is outpacing non-electrical growth.

    Skill tested: Must be True · how this choice captures the argument's function is the move to repeat next time.

    72% picked this

  4. In 1989 electrical energy constituted

    Unsupported

    This is a super strong claim that we can't prove. In one of our possible explanation worlds, electrical was up to 7.5 and coal was at 95. That's a possibility for 1989, and there's no way we'd say that electrical is responsible for GNP more than any other form of energy. Making a link to GNP goes beyond mere math and starts to get into causality we can't begin to speculate upon. Electrical energy's increase might be purely because of air conditioning, in which case it has nothing to do with GNP. That might be going up for a completely different reason.

    6% picked this

  5. In 1973 the electrical energy

    Unsupported

    This is a bold claim we can't prove. It's possible that in 1973, our energy portfolio looked like this: Overall: 100 megabits of energy Electric: 51 Coal: 40 Solar: 9 By 1989, electric has increased by more than 1/2, so let's say it's now around 80. We can make that work with the facts. Overall: 100 megabits of energy Electric: 80 Coal: 11 Solar: 9 Here's we've shown that electric can go up more than 50%, overall can go up less than 10% (it didn't go up at all), and yet in 1973 electric was more than all other energy combined and so quite well could have accounted for more GNP than all other energy combined.

    4% picked this

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