Reasoning · 1 checks · max 800 tokens · benched 2026-09-16
DeepSeek models side by side on "When does the faster train catch up?": DeepSeek V4.1 Flash scores 10/10; DeepSeek V4.1 Flash is the cheapest answer scoring 8+ at $0.06 per 1,000 runs. Outputs, checks, judge reasons, latency and cost.
System
Think carefully, then give only the final answer in the requested format.
User
Train A leaves a station at 09:10 travelling at a constant 80 km/h. Train B leaves the same station on the same track at 09:40 travelling at a constant 120 km/h in the same direction. How many minutes after 09:10 does train B catch up with train A? Reply with only the whole number of minutes.
Rubric for the judge: The single correct answer 90, with no working shown in the final output.
Every cell is one OpenRouter call at temperature 0 with the prompt's token cap and reasoning effort "low" where the model supports it. Cost is usage × the catalogue rate in models.json. Quality is one judge call to anthropic/claude-haiku-4.5 against the prompt's rubric, cached per prompt version.
deepseek/deepseek-v4-pro
91 in · 281 out (278 reasoning) · 1 words · checks 1/1
90
Judge: The output is exactly '90' with no extraneous commentary, matching the rubric requirement perfectly.
deepseek/deepseek-v4-flash
91 in · 471 out (468 reasoning) · 1 words · checks 1/1
90
Judge: The output is exactly '90' with no extraneous commentary, matching the rubric requirement perfectly.
deepseek/deepseek-v4.1-flash
117 in · 78 out (76 reasoning) · 1 words · checks 1/1
90
Judge: The output is exactly '90' with no extraneous commentary, matching the rubric requirement perfectly.
Reasoning: The single correct answer 90, with no working shown in the final output. The deterministic checks are exact.
If the judge's bar of 8/10 is good enough for you, DeepSeek V4.1 Flash at $0.06 per 1,000 runs. If you need the top score, DeepSeek V4.1 Flash at $0.06 per 1,000 runs.
Run it yourself
Re-run this prompt on DeepSeek with your own OpenRouter key, or tweak the wording and see what changes.
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