DNA analysis is the process in which genetic sequences are studied. It is used by law enforcement and medical personnel to identify a particular person or species, and even specific cancers and diseases. At one point the analysis process was very limited.
To round off to the nearest tenth, means to keep one decimal digit. (To round off to the nearest hundredth would mean to keep two digits; to the nearest thousandth, three; and so on. Now, the digit in the second decimal place is 5. Therefore add 1 to the previous digit 2.
Therefore, 51.7 rounded off to the nearest whole number as 52. The digit at the tenths place is 2 and 2 < 5. The digit at the ones place remains unchanged and the digits to the right of the decimal point means the tenths place and hundredths place becomes 0 (rounded down). Therefore, 147.28 rounded off to the nearest whole number 147.