
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
Given a sample size of 20, the data is grouped and the frequency for each group is as follows:
$(10,20)$, 2; $(20,30)$, 3; $(30,40)$, 4; $(40,50)$, 5; $(50,60)$, 4; $(60,70)$, 2.
Find the frequency of the sample data in the interval $(-\infty, 50)$.

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