Ravi obtained 70 and 75 marks in first two unit tests. Find the number of minimum marks he should get in the third test to have an average of at least 60 marks.

Explanation

To find the minimum marks Ravi should get in the third test to have an average of at least 60 marks, we can follow these steps:

### Step 1: Understand the average formula
The average of marks obtained in three tests is given by:
\[ \text{Average} = \frac{M_1 + M_2 + M_3}{3} \]
where \(M_1\), \(M_2\), and \(M_3\) are the marks obtained in the first, second, and third tests respectively.
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