To convert a teaspoon of liquid, such as a child's medicine, to milliliters, multiply the number of teaspoons by five. There are 4.93 ml., or cubic centimeters, in a teaspoon, so five is close enough. Because 3 tsp. are in 1 tbsp., a tablespoon is equal to roughly 15 ml.
Multiply the number of fluid ounces by 30 to get the number of milliliters, or cubic centimeters. There are 29.57 cubic centimeters for each U.S. fluid ounce, so this estimation is accurate.
To convert a gallon of liquid, such as gasoline or milk, to liters, multiply the number of gallons by four. A gallon is really equal to 3.7854 liters, but an estimation of 4 l to a gallon will only be off by 5 percent. A quart, which is 1/4 of a gallon, and a liter have almost exactly the same volume. A pint is roughly 1-/2 of a liter, while a cup is 1/4o f a liter.
Multiply the number of bushels by 35 to get the approximate number of liters. There are 35.23 liters per U.S. bushel.
To convert a cubic foot to liters, multiply by 30. The more precise conversion rate is 28.32 liters per cubic foot, but using an estimate of thirty will give you an error of less than 10%.