Question 1

How many centimeters are in an inch?

Accepted Answer

1 inch equals exactly 2.54 centimeters. Conversely, 1 cm is about 0.3937 inches. This conversion is especially useful for screen sizes (TVs, monitors, phones), clothing measurements, and height conversions. For example, a 65-inch TV has a diagonal of about 165 cm.

Question 2

How many kilograms are in a pound?

Accepted Answer

1 pound (lb) equals approximately 0.4536 kilograms, and 1 kg is about 2.2046 pounds. A quick mental shortcut: divide pounds by 2 and subtract 10% for a rough kg estimate. For example, 150 lbs / 2 = 75, minus 10% = 68 kg (actual: 68.04 kg). This is useful for airline baggage limits, gym weights, and body weight conversions.

Question 3

How do you convert Fahrenheit to Celsius?

Accepted Answer

Celsius = (Fahrenheit - 32) x 5/9. To convert Celsius to Fahrenheit: °F = °C x 9/5 + 32. Key reference points: water freezes at 32°F / 0°C, body temperature is 98.6°F / 37°C, and water boils at 212°F / 100°C. A quick mental trick: subtract 30 and divide by 2 for a rough °F-to-°C estimate (e.g., 80°F → (80-30)/2 = 25°C, actual: 26.7°C).

Question 4

How do you convert miles to kilometers?

Accepted Answer

1 mile equals approximately 1.6093 kilometers, and 1 km is about 0.6214 miles. A quick approximation: multiply miles by 1.6 to get kilometers. For example, 60 mph is about 96.6 km/h. This is essential for understanding speed limits, race distances (a marathon is 26.2 miles / 42.2 km), and travel distances when visiting countries using the metric system.

Question 5

What is the difference between US gallons and imperial (UK) gallons?

Accepted Answer

A US gallon is 3.785 liters, while an imperial (UK) gallon is 4.546 liters -- about 20% larger. This difference also affects fluid ounces: a US fluid ounce is 29.57 ml, while a UK fluid ounce is 28.41 ml. When reading fuel economy figures, UK MPG numbers will be higher than US MPG for the same vehicle due to the larger gallon. Always verify which gallon is being referenced.

Question 6

How do I convert cooking measurements between metric and US customary?

Accepted Answer

Common cooking conversions: 1 US cup = 236.6 ml (often rounded to 240 ml), 1 tablespoon = 14.8 ml, 1 teaspoon = 4.9 ml, 1 fluid ounce = 29.6 ml. For baking by weight: 1 cup of all-purpose flour = about 125g, 1 cup of sugar = about 200g. When following international recipes, measuring by weight (grams) is more accurate than by volume.

Question 7

What are the most important metric prefixes to know?

Accepted Answer

The key metric prefixes are: kilo (k) = 1,000 (1 km = 1,000 m), centi (c) = 1/100 (1 cm = 0.01 m), milli (m) = 1/1,000 (1 mm = 0.001 m), micro = 1/1,000,000, and mega (M) = 1,000,000. For data: 1 KB = 1,024 bytes, 1 MB = 1,024 KB, 1 GB = 1,024 MB, 1 TB = 1,024 GB. Understanding these prefixes makes all metric conversions intuitive.

From	To	Multiply By
Inches	Centimeters	2.54
Feet	Meters	0.3048
Yards	Meters	0.9144
Miles	Kilometers	1.6093
Nautical miles	Kilometers	1.852

From	To	Multiply By
Ounces (oz)	Grams	28.3495
Pounds (lb)	Kilograms	0.4536
US tons (short)	Metric tons	0.9072
UK tons (long)	Metric tons	1.0160
Troy oz (precious metals)	Grams	31.1035

From	To	Multiply By
US fluid oz	Milliliters	29.5735
US cups	Milliliters	236.588
US pints	Liters	0.4732
US gallons	Liters	3.7854
UK gallons	Liters	4.5461

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