General Educational Development (GED): Converting Measurements, Distance, Time, Speed, & Rates

Converting Measurements

Conversion Factor is the number or formula you need to convert a measurement in one set of units to the same measurement in another set of units. 

Example:

You are mixing some concrete for a home project, and you've calculated according to the directions that you need six gallons of water for your mix. But your bucket isn't calibrated, so you don't know how much it holds. On the other hand, you just finished a two-liter bottle of soda. If you use the bottle to measure your water, how many times will you need to fill it?

For this, I take the conversion factor of 1 gallon = 3.785 liters. This gives me:

= (6 × 3.785) liters = 22.71 L

Metric conversion charts and calculators for metric conversions 

Conversion charts and information

Unit Converter Express Version 

Online calculator for Converting units

Conversion Factors 

Information and list of conversion factors

To solve for distance use the formula for distance d = st, or distance equals speed times time.

distance = speed x time

Rate and speed are similar since they both represent some distance per unit time like miles per hour or kilometers per hour. If rate r is the same as speed s, r = s = d/t. You can use the equivalent formula d = rt which means distance equals rate times time.

distance = rate x time

To solve for speed or rate use the formula for speed, s = d/t which means speed equals distance divided by time.

speed = distance/time

To solve for time use the formula for time, t = d/s which means time equals distance divided by speed.

time = distance/speed