It is 500, and there is no need for decimal point.
Seventeen and one half thousand is numerically represented as 17,500.
1.5"
Half a milligramme = 0.5 milligramme
0.025
6.5
We write .5 or 0.5 as the decimal for one half.
The decimal of one thousand seventy thousandths is 1.07
12 and one half as a decimal is 12.5
You do not need a decimal point to write 34 thousand, but, if you must "34000." is one way.
100,000.0
71,000
1,500 one thousand five hundred
1.5
.5
101,000
Seventeen and one half thousand is numerically represented as 17,500.
1000.005