we have asked to represents
3 tenths and 9 hundredths as a decimal.
As we know the tenths place is the first place on right side of the decimal.
Also we know that hundredths is the second place on right side of the decimal.
since the problem says
3 tenths----> it mean the first position on the right side of the decimal.
9 hundredths.......> it mean the second position on the right side of the decimal.
Hence the decimal representation of the number is 0.39