Find out the missing term in the series `"…….."`7980,26970,63960,124950.

Answer

To find the missing term in the series "…….." 7980, 26970, 63960, 124950, we will analyze the pattern in the series step by step.

### Step 1: Identify the pattern in the series
We will look at the given terms and try to find a relationship between them. The terms are:
- 7980
- 26970
- 63960
- 124950

### Step 2: Analyze the terms
Let's examine the last term (124950) and see if we can find a pattern by working backwards.

### Step 3: Check the cube and subtraction pattern
From the video transcript, it suggests that the terms can be expressed in the form of cubes minus a number. We will check this hypothesis.

1. **For the last term (124950)**:
- It suggests using \(50^3 - 50\).
- Calculate \(50^3 = 125000\).
- Now, \(125000 - 50 = 124950\).

2. **For the third term (63960)**:
- It suggests using \(40^3 - 40\).
- Calculate \(40^3 = 64000\).
- Now, \(64000 - 40 = 63960\).

3. **For the second term (26970)**:
- It suggests using \(30^3 - 30\).
- Calculate \(30^3 = 27000\).
- Now, \(27000 - 30 = 26970\).

### Step 4: Find the first term
Now, we need to find the first term in the series. Following the same pattern:

- For the first term, we will use \(20^3 - 20\).
- Calculate \(20^3 = 8000\).
- Now, \(8000 - 20 = 7980\).

### Conclusion
Thus, the missing term before 7980 is \(20^3 - 20 = 7980\).

### Final Answer
The missing term in the series is **990**.