Class 8MathematicsRational NumbersFind the rational numbers ...

Find ten rational numbers between $-\tfrac{2}{5}$ and $\tfrac{1}{2}$.

Let us make the denominators the same, say $50$.  

$$-\tfrac{2}{5} = \frac{-2 \times 10}{5 \times 10} = -\tfrac{20}{50}$$  
$$\tfrac{1}{2} = \frac{1 \times 25}{2 \times 25} = \tfrac{25}{50}$$  

Ten rational numbers between $-\tfrac{2}{5}$ and $\tfrac{1}{2}$ = ten rational numbers between $-\tfrac{20}{50}$ and $\tfrac{25}{50}$.  

Therefore, ten rational numbers between $-\tfrac{20}{50}$ and $\tfrac{25}{50}$ are:  

$$-\tfrac{18}{50},\; -\tfrac{15}{50},\; -\tfrac{5}{50},\; -\tfrac{2}{50},\; \tfrac{4}{50},\; \tfrac{5}{50},\; \tfrac{8}{50},\; \tfrac{12}{50},\; \tfrac{15}{50},\; \tfrac{20}{50}$$

$-\tfrac{2}{5}$ और $\tfrac{1}{2}$ के बीच दस परिमेय संख्याएँ ज्ञात कीजिए।

हर को समान कर लेते हैं, मान लीजिए $50$।  

$$-\tfrac{2}{5} = \frac{-2 \times 10}{5 \times 10} = -\tfrac{20}{50}$$  
$$\tfrac{1}{2} = \frac{1 \times 25}{2 \times 25} = \tfrac{25}{50}$$  

$-\tfrac{2}{5}$ और $\tfrac{1}{2}$ के बीच दस परिमेय संख्याएँ = $-\tfrac{20}{50}$ और $\tfrac{25}{50}$ के बीच दस परिमेय संख्याएँ।  

अतः $-\tfrac{20}{50}$ और $\tfrac{25}{50}$ के बीच दस परिमेय संख्याएँ हैं:  

$$-\tfrac{18}{50},\; -\tfrac{15}{50},\; -\tfrac{5}{50},\; -\tfrac{2}{50},\; \tfrac{4}{50},\; \tfrac{5}{50},\; \tfrac{8}{50},\; \tfrac{12}{50},\; \tfrac{15}{50},\; \tfrac{20}{50}$$