Riddle Me This

Hidden so nobody spots the answers before playing. Quizmasters, this is for you.

1. 1. A weighing machine shows 12 kg. Adding a 3 kg parcel makes its accurate display show 9 kg. Nothing is removed. Which mode explains this?
   • A. Total mass
   • B. Mass still needed to reach a target (answer)
   • C. Heaviest parcel
   • D. Number of parcels
   A remaining-to-target display falls by 3 kg when 3 kg is added. It is not displaying total mass.
2. 2. A clerk sorts text labels character by character. Label 100 comes before label 20, correctly. Why?
   • A. Numerical sorting
   • B. Zeroes are ignored
   • C. Text sorting rather than numerical sorting (answer)
   • D. Largest number always goes first
   Text comparison examines the first differing character. The initial 1 comes before the initial 2.
3. 3. Two clear sheets each have an opaque black dot. Separately, two dots are visible. Stacked, just one is visible from above. Neither vanished. Why?
   • A. The dots overlap along the line of sight (answer)
   • B. Black ink becomes transparent
   • C. The lower dot turned white
   • D. The sheets exchanged their dots
   When aligned, the upper opaque dot hides the lower dot from that viewpoint.
4. 4. A conveyor carries a box east at 1 m/s. A robot drives west along its top at 1 m/s relative to the box. What does a stationary overhead camera see?
   • A. Robot moving east at 2 m/s
   • B. Robot moving west at 2 m/s
   • C. Robot moving west at 1 m/s
   • D. Robot staying in the same horizontal position (answer)
   The westward velocity relative to the box cancels the box's eastward velocity relative to the camera.
5. 5. An empty room counts visitors but excludes staff. Two people enter and neither leaves. The accurate visitor count stays at 1. What must be true?
   • A. Both are visitors
   • B. Exactly one is staff (answer)
   • C. Both are staff
   • D. One visitor was counted twice
   Two people are present, but only one counts as a visitor. Exactly one must be excluded as staff.
6. 6. A 100 cm plank must provide two pieces each exactly 50 cm. A saw removes 3 mm at every cut. Why does one central cut fail?
   • A. It adds 3 mm
   • B. Central cuts must be unequal
   • C. Only 99.7 cm of wood remains (answer)
   • D. The strip is counted twice
   The saw kerf consumes 0.3 cm. Only 99.7 cm remains, less than the 100 cm required.
7. 7. A courier drives away from a warehouse without turning or reversing, yet gets closer to the destination. Which explanation fits?
   • A. The destination is ahead along the outward road (answer)
   • B. Leaving any building approaches every destination
   • C. Warehouse and destination are identical
   • D. The odometer runs backwards
   The warehouse is not necessarily the destination. A destination ahead on the outward road gets closer.
8. 8. A display advances each second from 00 through 99, then resets to 00. Two seconds later its value is smaller. Which offered earlier value allows this?
   • A. 01
   • B. 49
   • C. 97
   • D. 98 (answer)
   Two advances after 98 give 99 and then 00. The other starting values do not cross the reset in two seconds.
9. 9. Fabric is folded into two layers and cut along a marked 40 cm line. Unfolded, it has two separate 40 cm cuts. Why?
   • A. Scissors doubled the line
   • B. The line lay over a second layer (answer)
   • C. Folding doubles every measurement
   • D. Unfolding lengthened one cut
   Cutting through two stacked layers makes a cut in each. Only the upper layer needs the guide line.
10. 10. A cinema has 80 seats. It correctly says SOLD OUT after selling 76 tickets, with no cancellations. Which explanation fits?
    • A. Every ticket counts twice
    • B. Sold out means every seat is occupied
    • C. Four seats are blocked from sale (answer)
    • D. Four tickets were secretly sold
    If four seats are blocked, selling the other 76 exhausts all seats available for purchase.
11. 11. A packed-item counter shows 41, 42, 43. One more item is packed, yet the accurate screen shows 42. Which change explains it?
    • A. It now shows items remaining in a batch of 86 (answer)
    • B. The batch size grew by one
    • C. It counts each item twice
    • D. It switched to binary
    After the next item, 44 are packed. In a batch of 86, exactly 42 remain, explaining a switch of displayed quantity.
12. 12. A ticket machine prints consecutive numbers, one per press. You receive 002; your next press gives 004. It skipped no number. Which explanation fits?
    • A. Two tickets are stuck together
    • B. It counts only even numbers
    • C. Someone else pressed once between your presses (answer)
    • D. 003 printed before 001
    An intervening press prints 003 before your next press prints 004. The sequence remains consecutive.