Which pair correctly matches tens and tenths in terms of prefix name and abbreviation?

Which pair correctly matches tens and tenths in terms of prefix name and abbreviation?

• A. Da and D
• B. Kilo and Milli
• C. Deca and Deci
• D. Hecto and Centi

Answer: (C)

In the metric system, prefixes denote powers of ten. Tens corresponds to 10^1, which is deca- and its symbol Da. Tenths correspond to 10^-1, which is deci- with the symbol d. So the pair that matches tens and tenths is Deca and Deci, using Da for ten and d for one tenth. Other pairings mix prefixes that represent different magnitudes (for example, 10^3 and 10^-3 for kilo and milli, or 10^2 and 10^-2 for hecto and centi), and a single-letter D isn’t an official SI symbol.

In the metric system, prefixes denote powers of ten. Tens corresponds to 10^1, which is deca- and its symbol Da. Tenths correspond to 10^-1, which is deci- with the symbol d. So the pair that matches tens and tenths is Deca and Deci, using Da for ten and d for one tenth. Other pairings mix prefixes that represent different magnitudes (for example, 10^3 and 10^-3 for kilo and milli, or 10^2 and 10^-2 for hecto and centi), and a single-letter D isn’t an official SI symbol.