Consider the following statement:
1. If both the terms of a ratio are multiplied or divided by the same natural number, then the ratio remains unaltered.
2. A statement which states that two ratios are equivalent is called proportion.
c. If 4 quantities are in proportion, the product of extremes is not equal to the means.
4. The mean proportion between any two numbers is equalto the square root of their product. The wrong one statements is /are:

Options

A. 1
B. 3
C. 3 and 4
D. 1 and 4

Answer

To determine which statements are incorrect, we will analyze each statement one by one.

### Step 1: Analyze the first statement
**Statement 1:** If both the terms of a ratio are multiplied or divided by the same natural number, then the ratio remains unaltered.

- **Explanation:** Consider the ratio 2:3. If we multiply both terms by 4, we get 8:12. The ratio 8:12 simplifies back to 2:3. Therefore, this statement is **correct**.

### Step 2: Analyze the second statement
**Statement 2:** A statement which states that two ratios are equivalent is called proportion.

- **Explanation:** If we have two ratios, say a:b and c:d, and they are equivalent (i.e., a/b = c/d), then we say that a:b is in proportion to c:d. Thus, this statement is also **correct**.

### Step 3: Analyze the third statement
**Statement 3:** If four quantities are in proportion, the product of extremes is not equal to the means.

- **Explanation:** For four quantities a, b, c, and d in proportion (a:b = c:d), the relationship holds that a * d = b * c (the product of the extremes equals the product of the means). Therefore, this statement is **incorrect**.

### Step 4: Analyze the fourth statement
**Statement 4:** The mean proportion between any two numbers is equal to the square root of their product.

- **Explanation:** The mean proportion between two numbers a and b is defined as √(a*b). This statement is **correct**.

### Conclusion
The incorrect statement is **Statement 3**.

### Final Answer
The wrong statement is: **Statement 3**.

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