您的購物車是空的
The decimal system of units
You have already learnt about \latex{ kilograms } and \latex{ kilometres }. \latex{ 1 } \latex{ kg = } \latex{ 1,000 } \latex{ g }, \latex{ 1 } \latex{ km = } \latex{ 1,000 } \latex{ m }.
The prefix \latex{ kilo } in the name of the quantities means thousand.
The prefix \latex{ kilo } in the name of the quantities means thousand.
The meanings of the prefixes \latex{ kilo }-, \latex{ hecto }-, \latex{ deka }-, \latex{ deci }-, \latex{ centi }-, \latex{ milli }- are as follows:
658295
prefix
symbol
meaning
prefix
meaning
symbol
\latex{ deka }
\latex{ hecto }
\latex{ kilo }
\latex{ mega }
\latex{ giga }
\latex{ G }
\latex{ M }
\latex{ k }
\latex{ h }
\latex{ da }
\latex{ ten }
\latex{ hundred }
\latex{ thousand }
\latex{ million }
\latex{ billion }
\latex{ deci }
\latex{ centi }
\latex{ milli }
\latex{ micro }
\latex{ nano }
\latex{ d }
\latex{ c }
\latex{ m }
\latex{ μ }
\latex{ n }
\latex{ tenth }
\latex{ hundredth }
\latex{ thousandth }
\latex{ millionth }
\latex{ billionth }
Note
In computer science:
\latex{ 1 } \latex{ byte } \latex{ = } \latex{ 8 } \latex{ bits }
\latex{ 1 } \latex{ kilobyte } \latex{ = 1,024 } \latex{ bytes }
\latex{ 1 } \latex{ megabyte } \latex{ = 1,024 } \latex{ kilobytes }
\latex{ 1 } \latex{ gigabyte } \latex{ = 1,024 } \latex{ megabytes }
Exercises
{{exercise_number}}. Convert the following quantities into \latex{ grams } and \latex{ centimetres }. Use the prefix table to help you.
a) \latex{ 1 } \latex{ centigram }
b) \latex{ 1 } \latex{ megametre }
c) \latex{ 1 } \latex{ hektometre }
d) \latex{ 1 } \latex{ dekametre }
e) \latex{ 1 } \latex{ decigram }
f) \latex{ 1 } \latex{ hektogram }
{{exercise_number}}. Convert the following units in a way that their quantity remains the same and their value becomes \latex{ 1 }. Use the appropriate prefixes.
a) one-hundredth of a \latex{ metre }
b) \latex{ 100 } \latex{ metres }
c) \latex{ 10 } \latex{ grams }
d) \latex{ 1,000 } \latex{ metres }
e) one-thousandth of a \latex{ metre }
f) one-millionth of a \latex{ gram }
{{exercise_number}}. Fill in the missing units and values.
a) ............ \latex{ km } \latex{ = 2,000 } \latex{ m }
b) ............ \latex{ g } \latex{ = 3 } \latex{ kg }
c) \latex{ 40 } \latex{ dm = } ............ \latex{ m }
d) \latex{ 5 } \latex{ m = } \latex{ 5,000 } ............
e) \latex{ 2 } \latex{ cm = } ............ \latex{ mm }
f) quarter \latex{ kg } \latex{ = 25 } ............
g) ............ \latex{ mm } \latex{ = 12 } \latex{ dm }
h) \latex{ 70 } \latex{ dkg = } ............ \latex{ g }
i) half \latex{ km } \latex{ = 50,000 }............
{{exercise_number}}. Which of the following statements are true and which are false?
a) \latex{ 1 } \latex{ km } is one-thousandth of \latex{ 1 } \latex{ m }.
b) \latex{ 1 } \latex{ dkg } is less than \latex{ 1 } \latex{ g }.
c) \latex{ 1 } \latex{ g } is \latex{ 100 } \latex{ mg }.
d) \latex{ 100 } \latex{ g } is \latex{ 1 } \latex{ kg }.
e) \latex{ 1 } \latex{ dm } is one-thenth of \latex{ 1 } \latex{ m }.
f) \latex{ 1 } \latex{ mm } is one-thousandth of \latex{ 1 } \latex{ m }.
{{exercise_number}}. Compare the following quantities using relation symbols.
a) \latex{ 6 } \latex{ km } ⬜ \latex{ 60,000 } \latex{ mm }
b) \latex{ 5 } \latex{ dm } ⬜ \latex{ 50 } \latex{ cm }
c) \latex{ 4 } and a half \latex{ km } ⬜ \latex{ 450 } \latex{ m }
d) \latex{ 73 } \latex{ kg } ⬜ \latex{ 7,300 } \latex{ g }
e) \latex{ 3,000 } \latex{ cm } ⬜ \latex{ 3 } \latex{ km }
f) \latex{ 1,500 } \latex{ mm } ⬜ \latex{ 15 } \latex{ m }
g) \latex{ 500 } \latex{ g } ⬜ \latex{ 5 } \latex{ kg }
h) \latex{ 9,200 } \latex{ kg } ⬜ \latex{ 92 } \latex{t }
i) \latex{ 80,000 } \latex{ g } ⬜ \latex{ 800 } \latex{ mg }
Quiz
One thousand times how many \latex{micrometres} equals one \latex{kilometre?}
