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Question 1 · Sep 27 · Day 18

Gemini on Question 1, Sep 27

Is 91 a prime number? Think step by step and then answer "[Yes]" or "[No]".

To determine if 91 is a prime number, we can check if it is divisible by any prime numbers smaller than its square root (the square root of 91 is approximately 9.5).

  • 1.Check 2: 91 is not an even number (it doesn't end in 0, 2, 4, 6, or 8), so it is not divisible by 2.
  • 2.Check 3: The sum of the digits of 91 is 9 + 1 = 10. Since 10 is not divisible by 3, 91 is not divisible by 3.
  • 3.Check 5: 91 does not end in 0 or 5, so it is not divisible by 5.
  • 4.Check 7: Let's divide 91 by 7.
    7 × 10 = 70.
    91 - 70 = 21.
    7 × 3 = 21.
    Therefore, 7 × 13 = 91.

Since 91 can be divided evenly by 7 and 13, it has factors other than 1 and itself. Therefore, it is a composite number, not a prime number.

[No]

sha256 2753a1829402… · 22 tokens in · 742 out · 6.7 s · via Google · stopped on its own

Sep 27, the whole dayQuestion 1, every day

Exact recordShowHideThe model id, the run, the verbatim text with line numbers and its full sha256
Model
google/gemini-3.1-pro-preview
pinned google/gemini-3.1-pro-preview-20260219; alias resolved to google/gemini-3.1-pro-preview-20260219 at 2026-09-27 09:00:07 UTC (matches the pin)
Date
2026-09-27 · run 20260927T090007Z-7adb14 · scorer v1
Scored
answered · correct · format ok
sha256
2753a18294023e63814c2caf1333e6b0e590b0437e135ea3c0f46acce6ec2dfd
Permalink
https://modeldrift.watch/r/2026-09-27/D1/google/gemini-3.1-pro-preview/
Scored
answered · correct · format ok
Received
2026-09-27 09:00:21 UTC
Run
20260927T090007Z-7adb14
Served by
Google · HTTP 200 · finish stop
Size
729 characters · 742 tokens out incl. hidden reasoning · 6.7 s

Highlighted: the last [Yes]/[No] bracket, which is the scored answer (No).

To determine if 91 is a prime number, we can check if it is divisible by any prime numbers smaller than its square root (the square root of 91 is approximately 9.5).
1. **Check 2:** 91 is not an even number (it doesn't end in 0, 2, 4, 6, or 8), so it is not divisible by 2.
2. **Check 3:** The sum of the digits of 91 is 9 + 1 = 10. Since 10 is not divisible by 3, 91 is not divisible by 3.
3. **Check 5:** 91 does not end in 0 or 5, so it is not divisible by 5.
4. **Check 7:** Let's divide 91 by 7.
7 × 10 = 70.
91 - 70 = 21.
7 × 3 = 21.
Therefore, 7 × 13 = 91.
Since 91 can be divided evenly by 7 and 13, it has factors other than 1 and itself. Therefore, it is a composite number, not a prime number.
[No]

End of response · 14 lines · 729 characters · sha256 2753a18294023e63814c2caf1333e6b0e590b0437e135ea3c0f46acce6ec2dfd