Self-study
Support If a child is to develop healthy bones, the child's diet must include sufficient calcium. ██ █████████ ███████ ████ ███ █████ ██ ████████ ███ ██ ███ ███████ ███████ █████ ██ ███ ███████ ██████████ ████████
Method of Reasoning
The argument presents a conditional relationship. It then concludes that the absence of the sufficient condition leads to the absence of the necessary condition.
Identify and Describe Flaw
This argument features the cookie-cutter flaw of confusing a sufficient condition for a necessary condition. It’s still entirely possible to have the necessary condition (enough calcium) without having the sufficient condition (healthy bones), so the absence of the sufficient condition doesn’t support any conclusions.
9.
Flawed reasoning in which one ██ ███ █████████ ████ ███████ █████████ ███ ██████ █████████ ██ ███ ████████ ██████
a
If bread is ██ ████ █ ████ ██████ ██ ████ ██ █████ ██ ███ █████ ████████████ ██ █████████ ███████ ████ █████ ████ ██ ███ █████ ██ ███ █████ ███████████ ████ ███ ████ █ ████ ██████
No flaw. (A) presents a conditional relationship: if firm crust, then baked at the right temperature. It then validly concludes that the absence of the necessary condition leads to the absence of the sufficient condition.
b
A cake must ███████ ███ █████ ██████ ██ █████ ██ █████ ██ █████ █████ ██ █████████ ███████ ████ █████ ████ ██ ███ █████ ████ ██ ███ ███████ ███ █████ ██████ ██ ██████
(B) presents a conditional relationship: if a cake tastes good, then it has the right amount of flour. It then invalidly concludes that the absence of the sufficient condition (not tasting good) leads to the absence of the necessary condition (not having the right amount of flower). The stimulus also invalidly concludes that the absence of a sufficient condition leads to the absence of a necessary condition, so (B) matches.
c
The Bake-a-Thon, which ██ ████ ██ ███████████ ██ ███ █████ ███ █████ ████ ███ ██ █ ██████ █████ ███ ███ ██ ███ ██ █████████ ███████ ████ ███ ██████ ██ ████ ██████ ███████████ ████ ███ ██ █████ ███ ███ ██ ███
Wrong flaw. (C) presents a past trend (no winners being under 30), then invalidly concludes it will continue to be true in the future. The stimulus, meanwhile, invalidly concludes that the absence of a sufficient condition implies the absence of a necessary condition, so (C) doesn’t match.
d
Both yeast and ██████ ██████ ███ █████ █████ █████ ██ █████ ██ █████████ ███████ ████ █████ ███ ██████ ██ ███████████ ███ ██████ ██████ ██ █ ██████ ███ █████ ██████
Wrong flaw. (D) gives a single similarity between yeast and baking powder (they both cause sweet rolls to rise), and then invalidly concludes that they must be similar in another way (yeast can replace baking powder in sweet roll recipes) The stimulus, meanwhile, invalidly concludes that the absence of a sufficient condition implies the absence of a necessary condition, so (D) doesn’t match.
e
In recipe contests, █████ ███ ██████ ████ ███████████ ██ ███ ███ ████████ ████ █████ ███ ██ ███ ████ █████████ ██ █████████ ███████ ████ ███████████ █████████ ████ █ ██████ ██████ ██ ███████ ██ ███ ████ ████████ ████ ██ ███ ███ █████████
No flaw. If there’s less competition in cake contests when compared to pie contests, contestants will generally have a better chance of winning a cake contest.