Thinking Skills Mock Test 2: 2026 NSW Selective Format

Question 1 · Multiple choice

Question

Options

• A. 72
• B. 78
• C. 84
• D. 90

Correct answer

A. 72

Explanation

Out of 156 sheep, all but 12 gave birth. So the number of sheep that had lambs is: 156 - 12 = 144 Let: x = sheep with exactly 1 lamb y = sheep with exactly 2 lambs Then: x + y = 144 because 144 sheep had lambs altogether. The total number of lambs was 216, so: x + 2y = 216 Now subtract the first equation from the second: (x + 2y) - (x + y) = 216 - 144 y = 72 So 72 sheep had 2 lambs. That means: x = 144 - 72 = 72 So 72 sheep had exactly one lamb. Method 2: If all 144 sheep had exactly one lamb, there would be 144 lambs. But there were actually 216 lambs, which is 72 extra lambs. Each sheep with 2 lambs adds 1 extra lamb, so 72 sheep had 2 lambs. That leaves 72 sheep with 1 lamb.

Question 2 · Multiple choice

Question

Options

• A. Sphere
• B. Cylinder
• C. Cone
• D. Pyramid

Correct answer

C. Cone

Explanation

We need a solid that: looks like a triangle from the side, and looks like a circle from above. A cone fits both clues. From above, you see its circular base, so it looks like a circle. From the side, it has a pointed shape, so it looks like a triangle. Check the other options: A sphere looks like a circle from almost every angle. A cylinder looks like a rectangle from the side. A pyramid would not look like a circle from above. So the shape must be a cone.