It is 11.0012
It is 12.403
Seven and seven hundred twelve thousandths would be written as 7.712The "and" tells you where the decimal goes, "thousandths" tells you how many places there will be in the decimal part of your answer (3 decimal places for thousandths), and seven hundred twelve tells you how many thousandths there will be.
Twelve and eight hundred seventy-three thousandths
Twelve thousand and twelve thousandths written as a decimal is 12000.012
Seven hundred forty-five and nine hundred twelve thousandths
Seven hundred forty-five and nine hundred twelve thousandths.
0.512 = five hundred twelve thousandths.