Find the solution of the following equations by trial-and-error method.
`3a=750`

Answer

To solve the equation \(3a = 750\) using the trial-and-error method, we will follow these steps:

### Step-by-step Solution:

1. **Understand the Equation**:
We need to find the value of \(a\) such that when multiplied by 3, it equals 750.

2. **Start with an Initial Guess**:
Let's start by guessing a value for \(a\). Since 750 is a large number, we can start with a value that is a multiple of 10.

3. **First Guess**:
Let's try \(a = 50\).
\[ 3 \times 50 = 150 \]
This is not equal to 750.

4. **Second Guess**:
Now, let's try \(a = 100\).
\[ 3 \times 100 = 300 \]
This is still not equal to 750.

5. **Third Guess**:
Next, let's try \(a = 150\).
\[ 3 \times 150 = 450 \]
This is not equal to 750.

6. **Fourth Guess**:
Now, let's try \(a = 200\).
\[ 3 \times 200 = 600 \]
This is still not equal to 750.

7. **Fifth Guess**:
Let's try \(a = 250\).
\[ 3 \times 250 = 750 \]
This is equal to 750.

8. **Conclusion**:
We have found that when \(a = 250\), the equation \(3a = 750\) holds true.

### Final Answer:
The solution to the equation \(3a = 750\) is \(a = 250\).

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