For approximations, it may be useful to remember the following:

 1 centimeter = .4 in. (nearly). 1 meter = 40 in. (roughly). 1 kilometer = 5/8 mile (nearly). 1 liter = 1 liquid quart (nearly). 1 liter = 1/8 peck (nearly). 1 gram = 15.4 grains. 1 kilogram = 2 1/5 pounds.

To convert metric measures into U. S. measures, by use of the preceding tables, find the desired equivalent in measure of a metric unit of the denomination given, and multiply this equivalent by the metric number. For example, it is desired to find the equivalent in pounds of 19.6 kilos. From the table of weights, 1 kilo = 2.2046 lb.; hence, 19.6 kilos = 2.2046 X 19.6 = 43.21 lb. In similar manner, 8 liters expressed in U. S. gallons = .264179X8 = 2.113432 gal.

To convert U. S. measures into metric measures, find how much a metric unit of the desired denomination is equal to in U. S. measure, and divide the given number by this equivalent. For example, it is desired to convert 4 1/2 miles into kilometers. From the table of lengths, it is found that a kilometer is .621 mi.; hence, dividing 4.5 by .621, the result is 7.24 kilometers.

Other useful conversion factors are as follows:

### Length

1 in. = .0254 meter; 1 ft. = .3048 meter; 1 yd. = .9144 meter; 1 mi. = 1,609.34 meters = 1.609 kilometers.

### Area

1 sq. in. = .000645 square meter; 1 sq. ft. = .0929 square meter; 1 sq. yd. = .836 square meter; 1 acre = 4,047 square meters.

### Capacity

1 cu. in. = .0164 liter; 1 U. 8. bushel = 35.24 liters; 1 U. S. dry quart = 1.101 liters; 1 U. S. peck = 8.81 liters; 1 cu. yd. = 765 liters; 1 U. S. liquid quart = .9465 liters ; 1 U. S. gallon = 3.785 liters.

### Weight

1 grain = .0648 gram; 1 avoirdupois ounce = 28.349 grams; 1 Troy ounce = 31.103 grams; 1 avoirdupois pound = 453.59 grams.