CTET Paper II (Mathematics and Science) Dec 2018 Solved Paper

Concept:Closure property means that when you perform an operation on two numbers from a set, the result always belongs to the same set.Explanation:Here, we have two rational numbers: $\frac{3}{7}$ and $\frac{-7}{8}$.Their sum is $\frac{3}{7} + \frac{-7}{8} = \frac{24 - 49}{56} = \frac{-25}{56}$.The result $\frac{-25}{56}$ is also a rational number.Since the sum of two rational numbers is rational, this demonstrates that rational numbers are closed under addition.Answer:A. rational numbers are closed under addition