State whether the given statement is true or false :
If C is the set of all prime numbers , less than 80, then ` 57 in C .`

Answer

To determine whether the statement "57 is in set C" is true or false, where C is the set of all prime numbers less than 80, we can follow these steps:

### Step-by-Step Solution:

1. **Define Prime Numbers**:
- A prime number is defined as a natural number greater than 1 that has no positive divisors other than 1 and itself.

2. **List Prime Numbers Less Than 80**:
- We will list all prime numbers that are less than 80. The prime numbers less than 80 are:
- 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79.

3. **Check if 57 is a Prime Number**:
- To check if 57 is a prime number, we need to find its divisors.
- The number 57 can be divided by 1, 3, 19, and 57. Since it has divisors other than 1 and itself (specifically, it is divisible by 3 and 19), it is not a prime number.

4. **Determine Membership in Set C**:
- Since 57 is not a prime number, it cannot be a member of set C (the set of all prime numbers less than 80).

5. **Conclusion**:
- Therefore, the statement "57 is in C" is false.

### Final Answer:
The statement is **False**.

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