a)
\(3\frac{2}{5}=3,4\)
\(12\frac{3}{4}=12,75\)
\(6\frac{1}{2}=6,5\)
b)
\(1,245=\frac{249}{200}\)
\(45,2=\frac{226}{5}\)
\(20,15=\frac{403}{20}\)
a 3 2/5=1,7
12 3/4=5,1
6 1/2=1,3
b 1,245=1 245/1000
45,2=45 2/10
20,15=20 15/100
a] 3,4 12,75 6,5
b] 1245/1000 452/10 2015/100