PrepTest 117

Incorrect. The stimulus compares adult bird size to egg size, not the ratio of the volume of the egg and the weight of the egg.

Incorrect. While the smaller birds have an egg with a weight ratio compared to the adult bird that's greater, this doesn't mean that the egg weighs more than in species with a smaller ratio. As a quick example, if a hummingbird weighs 1 pound, its egg would be .15 pounds; if the goose is 20 pounds, its egg would be .8 pounds. That weighs more despite the lower percentage. (Short version? Don't confuse percents and amounts!)

Correct. Argument or Facts:
Facts

Question Type:
Illustration

Stimulus Summary:
Hummingbird — Very small, with an egg 15% of its weight
Goose — Bigger, with an egg 4% of its weight
Ostrich — Biggest, with an egg 1.6% of its weight

Answer Anticipation:
There are a few questions on the LSAT that follow this general form—they provide three data points, and they ask us to connect them. We need to account for all of the data in whatever answer we select.

Luckily here, there's no weirdness in the numbers—they always move in the same direction. As the bird gets bigger, the size of the bird's egg compared to its total size gets smaller. The correct answer will therefore reflect this.

Answer Explanation:
This answer tracks the data from the stimulus. The larger the bird, the smaller the ratio.

Key Takeaway:
When a stimulus presents three data points, see what relationship persists through all of them. The correct answer will likely reflect this similarity.

Incorrect. We can't tell that the size and volume actually vary greatly from bird to bird—the eggs may all be about the same size and weight, representing different percentages of birds of different sizes.

Incorrect. We don't know how much the egg size varies since the stimulus discusses it in terms of percentage of adult birds.