Since the United States' temperatures operate on the Fahrenheit scale while Greece's operate on the Celsius scale, you'll need to know how to make simple conversions between these two measurement systems before you travel in order to properly pack for your trip.
Say it will be 24 degrees Celsius in Athens, Greece tomorrow. Do you grab a sweater or strip down to your bathing suit? One easy way to know is to subtract two from the degrees Celsius, multiply the result by 2, and add 30 to the product. For the case of 24 degrees Celsius, you would subtract two (22), then multiply by 2 (44), then add 30 to get 74 F.
On the other hand, converting from Fahrenheit to Celsius requires that you first subtract 30 from the number, then divide the result by 2, and finally add 2 to that quotient—basically the opposite of converting from Celsius to Fahrenheit.
However, keep in mind both of these simple conversions only get you within a few degrees Fahrenheit or Celsius of the actual temperature, which should give you a basic idea of what the weather calls for in terms of clothing.
Exact Conversions Between Fahrenheit and Celsius
If you'd rather know exact Grecian temperatures in Fahrenheit (and don't want to use an online converter or app that gives temperature in Fahrenheit), you can accurately convert from Celsius by multiplying the degrees by 9/5 and then adding 32 to the result.
(9/5)C + 32 = F
To convert degrees Fahrenheit back into degrees Celsius by this method, you would first subtract 32 from the degrees Fahrenheit, then multiply the result by 5/9 instead.
(F-32)*5/9 = C
Alternatively, if you just want a simple way to know what to pack, you could find out the average temperatures and weather conditions you can expect year-round in Greece. Or, if you're carrying your smartphone around with you in Greece, check those roaming charges and international data plans then download a simple temperature converter app.
Other Conversions for Travel to Greece
Degrees aren't the only units of measurement that need converting when traveling from the United States to Greece. You'll also need to know how to convert currency values between U.S. dollars and the Grecian Euro; American miles to European kilometers; and even U.S. ounces, pints, and quarts to Grecian liters and milliliters.
Fortunately, not too many details of travel in Greece require such mathematical skill, but it can still be helpful to know how to figure out a few things on your own. You may want to learn to roughly calculate the current dollar-Euro exchange or other exchange rates in your head as these can be convenient when making purchases; though, you can also find cell phone apps online which make doing so a breeze.
When trying to calculate distance, keep in mind that miles are longer than kilometers: one kilometer equals approximately 0.6214 miles. While a day trip outside of Athens may seem distant at 50 kilometers, for instance, it's actually just over 30 miles from the city. Whether you're taking a short trip around Greece or planning on flying out of one of its many airports, you'll want to know how far you need to go in a measurement system you can understand.