Median real estate property taxes paid for housing units with mortgages in 2013: $590 (1.2%). Median real estate property taxes paid for housing units with no mortgage in 2013: $637 (1.5%). Nearest city with pop. 50,000+: Bismarck, ND (78.6 miles, pop. 55,532). Nearest city with pop. 200,000+: Minneapolis, MN (305.7 miles, pop. 382,618).
The third type of variable is a controlled variable. This variable is constant in an experiment. Experiments are repeated a number of times to interpret how a change in the independent variable affects each trial result.
Unit 4 - Controlled Variable. In scientific investigations there are three types of variable. Key independent variable (what we change), dependent variable (what we measure) and the controlled variables (factors we control and ensure are the same each time we do the experiment).Controlled variables make sure that the experiment is a fair test.Controlled variables are... 1  all of the factors.ey independent variable (what we change), dependent variable (what we measure) and the controlled variables (factors we control and ensure are the same each time we do the experiment). Controlled variables make sure that the experiment is a fair test. Controlled variables are... 1  all of the factors.