Many measurements in the United States are made in metric units. A drink may come in 2-liter bottles, calcium may come in 500-mg capsules, and we may run a 5-K race. To work easily in both systems, we need to be able to convert between the two systems.
The reference table below shows some of the most common conversions.
example
Lee’s water bottle holds
500 mL of water. How many fluid ounces are in the bottle? Round to the nearest tenth of an ounce.
Solution
|
500 mL |
Multiply by a unit conversion factor relating mL and ounces. |
500mL⋅30mL1fl oz |
Simplify. |
30500fl oz |
Divide. |
16.7fl. oz. |
|
The water bottle holds 16.7 fluid ounces. |
Exercises
Soleil lives in Minnesota but often travels in Canada for work. While driving on a Canadian highway, she passes a sign that says the next rest stop is in
100 kilometers. How many miles until the next rest stop? Round your answer to the nearest mile.
Answer:
Solution
|
100 kilometers |
Multiply by a unit conversion factor relating kilometers and miles. |
100kilometers⋅1.61kilometers1mile
100⋅1.61km1mi |
Simplify. |
1.61100mi |
Divide. |
62 mi |
|
It is about 62 miles to the next rest stop. |
Temperature Conversion
To convert from Fahrenheit temperature,
F, to Celsius temperature,
C, use the formula
C=95(F−32)
To convert from Celsius temperature,
C, to Fahrenheit temperature,
F, use the formula
F=59C+32
Exercises
Convert
50∘F into degrees Celsius.
Answer:
Solution
We will substitute 50∘F into the formula to find C.
Use the formula for converting °F to °C |
C=95(F−32) |
Substitute 50 for °F. |
C=95(50−32) |
Simplify in parentheses. |
C=95(18) |
Multiply. |
C=10 |
|
A temperature of 50°F is equivalent to 10°C. |
example
The weather forecast for Paris predicts a high of
20∘C Convert the temperature into degrees Fahrenheit.
Answer:
Solution
We will substitute 20∘C into the formula to find F.
Use the formula for converting °F to °C |
F=59C+32 |
Substitute 20 for °C. |
F=59(20)+32 |
Multiply. |
F=36+32 |
Add. |
F=68 |
|
So 20°C is equivalent to [latex]68^{\circF. |