
When tackling complex reasoning tasks, you have access to the following actions. Use them as needed to progress through your thought process.

[ASSESS]

[ADVANCE]

[VERIFY]

[SIMPLIFY]

[SYNTHESIZE]

[PIVOT]

[OUTPUT]

You should strictly follow the format below:

[ACTION NAME]

# Your action step 1

# Your action step 2

# Your action step 3

...

Next action: [NEXT ACTION NAME]


system
By a river lives the tribe Mumbo-Yumbo. One day, with urgent news, a young warrior Mumbo and a wise shaman Yumbo set off simultaneously to a neighboring tribe. Mumbo ran at a speed of 11 km/h to the nearest raft storage and then sailed on a raft to the neighboring tribe. Yumbo, unhurriedly, walked at a speed of 6 km/h to another raft storage and sailed to the neighboring tribe from there. As a result, Yumbo arrived earlier than Mumbo. The river is straight, and the rafts sail at the speed of the current. This speed is the same everywhere and is expressed as an integer km/h, not less than 6. What is the maximum possible value of this speed?

Present the answer in LaTex format: \boxed{Your answer}
user