OC Thinking Skills Practice Test 6 — 2027 NSW Opportunity Class Exam

The fact: Most gum trees worldwide grow in Greenvale National Park.

This tells us: among ALL gum trees in the world, the majority are located in Greenvale.

Check Ravi: "A random gum tree is probably in Greenvale." If you randomly pick one gum tree from all gum trees worldwide, the majority of those trees are in Greenvale — so your randomly chosen gum tree is most likely in Greenvale. This follows directly from the fact. Ravi is correct ✓.

Check Luca: "A random tree IN Greenvale is probably a gum tree." Luca is making a different claim: that gum trees make up the majority of trees inside Greenvale. But the fact only tells us about WHERE most of the world's gum trees are — not about what proportion of Greenvale's trees are gum trees. Greenvale could be a vast park containing millions of other tree species and still hold "most" of the world's gum trees. The fact does NOT tell us the composition of Greenvale's forest. Luca is wrong ✗.

Answer: Ravi only.

Looking down from above, each horizontal "slice" of the solid appears as a circle (or nested circles) when the shape is rotationally symmetric about a vertical axis.

The wide middle part (the tall rectangle in the side view) is like a cylinder — from the top it is one large circle.

The top frustum (trapezoid in side view) has a smaller circular top face and a larger circular bottom face; from above you see both radii as two smaller concentric circles inside the cylinder's rim.

The bottom sphere is narrower than the cylinder; its circular outline sits inside the cylinder's circle and merges with the nested rings you see from the frustum, giving three visible circular boundaries — three concentric circles.

B only shows two circles (too few). C and D mix squares or a trapezoid with the plan, which does not match a round top view of this stack.

So A is correct.