Problem 9 · Infer and test an addition rule · 3 points
Made by AI and not reviewed by a real person.
Mia’s number machine makes 1, 4 → 6; 3, 5 → 11; and 4, 2 → 10. Which ticket does not follow its secret rule?
- 2, 4 → 8
- 5, 3 → 11
- 3, 2 → 8
- 5, 1 → 11
- 6, 3 → 15
Show a hint
- Add the two inputs in each example. How much more do you need to reach the output?
- Look for which input gets added a second time, then check every ticket.
Show the answer and solution
Answer: B — 5, 3 → 11
The machine adds the first input twice and the second input once: 1+1+4=6, 3+3+5=11, and 4+4+2=10. So 5, 3 → 11 does not fit: 5+5+3=13. It is tempting because 3, 5 → 11 works, but swapping the inputs changes the result. The other tickets give 8, 11, 15, and 8 as shown.