4/5 + 0,3 =; 0,45 − 1/4 =; 1/20 + 0,25 =; 1/8 − 1/9 =; 13/20 + 0,4 =

1. \(\frac{4}{5}+0.3=0.8+0.3=1.1\).
2. \(0.45-\frac{1}{4}=0.45-0.25=0.2\).
3. \(\frac{1}{20}+0.25=0.05+0.25=0.3\).
4. \(\frac{1}{8}-\frac{1}{9}=\frac{9-8}{72}=\frac{1}{72}\).
5. \(\frac{13}{20}+0.4=0.65+0.4=1.05\).

Ответ: \(1.1;\ 0.2;\ 0.3;\ \frac{1}{72};\ 1.05\).