3) 3 19/25 − 1 11/20 =

\(3\dfrac{19}{25}-1\dfrac{11}{20}=2+\left(\dfrac{19}{25}-\dfrac{11}{20}\right)\)

\(\dfrac{19}{25}-\dfrac{11}{20}=\dfrac{76-55}{100}=\dfrac{21}{100}\)

Ответ: \(2\dfrac{21}{100}\)