\(20+\dfrac{5}{10}+\dfrac{3}{100}\\ =\dfrac{20.100}{100}+\dfrac{5.10}{100}+\dfrac{3}{100}\\ =\dfrac{2000+50+3}{100}=\dfrac{2053}{100}=20,53\)
20+\(\dfrac{5}{10}\)+\(\dfrac{3}{100}\)=\(\dfrac{20}{10}\)+\(\dfrac{5}{\text{}\text{}\text{}\text{}\text{}\text{}10}\)+\(\dfrac{3}{100}\) =\(\dfrac{25}{10}\)+\(\dfrac{3}{100}\)=\(\dfrac{253}{100}\)
20,53