3.6 because the 6/10 part is like saying .60 and you can choose to add the zero or leave it out
3.6
3.6
56.3 !
23.6
6.3
3.6
203.6
56.3
Twenty three and six tenths
One thousand six hundred twenty and three tenths in decimal form is: 1,620.3
3 and 6/10 = 3.6 as a decimal
five and six tenths in decimal = 5.6