
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
A school has a total of 490 teachers, of which 350 are under 40 years of age, and 140 are 40 years or older. To understand the situation of Mandarin promotion and popularity, the school decides to use stratified sampling to draw a sample of 70 teachers for a Mandarin proficiency test. How many teachers under the age of 40 should be selected for the sample?

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