# Quick ‘n Easy Conversions – The Article Flotsam and jetsam: Just more shmata, drek or occasionally useful stuff, nu?

Trash and treasure really are in the eye of the beholder.

What follows is an egocentric (living?) collection of odds and ends.

As a science guy, people have asked if there is

 “Is there a quick way to convert kg, kilo, liters, etc to US units?“

Can you remember how to add or subtract 10%?

3 kg x 2 = 6 … 10% of 6 = 0.6 … 0.6 + 6 = 6.6

Lbs to Kg: Subtract 10% from pounds and Divide by 2
5 kg -10% = 4.5 … 4.5 / 2 = 2.25

Meters to Yards: Add 10% to Meters to get Yards
5 Meters + 10% = 5.5 Yards

Yards to Meters: Subtract 10% from Yards to get Meters
5 yards – 10% = 4.5 meters

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Can you remember how to add or subtract 5%?

Gallons to Liters: Multiply Gallons x 4 and then Subtract 5%
10 Gal. x 4 = 40 … 5% of 40 = 2… 40 – 2 = 38 Liters

Liters to Gallons: Divide Liters by 4 and then Add 5%
10 L / 4 = 2.5 … 2.5 + 0.125 = 2.63 Gal

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Miles to Km (or Miles per hr to Km per hour) – double and subtract 20%.
55 mph x 2 = 110 … 20% of 110 is 22 .. 110 – 22 = 88 kph => this is the more accurate version (99.5% accurate).

Km per hr to Miles per hr: Divide kph by 2 and add 25% – ( or 1/4) – then round up
100 kph / 2 = 50 … 25% of 50 = 12.5 … 50 + 12.5 = 62.5 mph (2.3% error)

All of these methods get you within 99% of the correct answer, (except the last one) …

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Feel free to copy while giving proper attribution: YucaLandia/Surviving Yucatan.
Steven M. Fry