Given below is the frequency distribution table regarding the concentration of sulphur dioxide in the air in parts per million of a certain city for 30 days.
Conc. of `S O_2` 0.00-0.04 0.04-0.08 0.08-0.12 0.12-0.16 0.16-0.20 0.20-0.24
No of days: 4 8 9 2 4 3 Find the probability of concentration of sulphur dioxide in the interval 0.12-0.16 on any of these days.

Explanation

To find the probability of the concentration of sulphur dioxide (SO₂) in the interval 0.12-0.16 parts per million (ppm) over a period of 30 days, we can follow these steps:

### Step 1: Identify the total number of days
We are given that the total number of days is 30.

### Step 2: Identify the frequency of the interval 0.12-0.16
From the frequency distribution table:
- The interval 0.12-0.16 has a frequency of 2 days.
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