(i) $$\dfrac{3}{7}= \dfrac{....}{35}$$
The denominator in the second fraction is $$35$$.
To get $$35$$ from $$7$$, we have to multiply $$7$$ by $$5$$.
So, $$\dfrac{3}{7} = \dfrac{3 \times 5}{7 \times 5} = \dfrac{15}{35}$$
(ii) $$\dfrac{5}{....} = \dfrac{30}{18}$$
To make both fractions equal, we multiply the numerator of the first fraction by $$5$$.
The numerator its the first fraction is $$5$$. To get $$5$$ from $$30$$, we have to divide $$30 \div 6$$.
So $$\dfrac{30 \div 6}{18 \div 6}= \dfrac{5}{3}$$
$$\therefore \dfrac{5}{3} = \dfrac{30}{18}$$
(iii) $$\dfrac{...}{9} = \dfrac{56}{72}$$
The denominator in the second fraction is $$72$$ and the denominator in the first fraction $$9$$.
To get $$9$$ from $$72$$, we have to divide $$72 \div 8$$
To make both fractions equal, we divide the numerator of the second fraction y $$8$$.
So, $$\dfrac{56 \div 8}{72 \div 8} = \dfrac{7}{9}$$
$$\therefore \dfrac{7}{9}= \dfrac{56}{72}$$