**Improper Fractions**

An improper fraction is a fraction in which the numerator (the number on top) is equal to or greater than the denominator (the number on the bottom). In other words, the numerator is larger than or equal to the denominator.

Let's analyze each fraction from the given options to determine if it is an improper fraction or not.

1. 2/7:
- The numerator is 2, and the denominator is 7.
- Since the numerator is smaller than the denominator, 2/7 is not an improper fraction.

2. 1/2:
- The numerator is 1, and the denominator is 2.
- Similar to the previous fraction, 1/2 is also not an improper fraction.

3. 2/3:
- The numerator is 2, and the denominator is 3.
- Once again, the numerator is smaller than the denominator, so 2/3 is not an improper fraction.

4. 73/10:
- The numerator is 73, and the denominator is 10.
- In this case, the numerator is significantly larger than the denominator.
- Therefore, 73/10 is an improper fraction.

**Conclusion**

Out of the given fractions, only 73/10 is an improper fraction. The numerator, 73, is greater than the denominator, 10. The other fractions, 2/7, 1/2, and 2/3, are not improper fractions because their numerators are smaller than their denominators.

73/10 because 73 is bigger than 10 and if numerator is bigger than denominator it is called improper fraction