Exam Questions and CORRECT Answers
Percent (relative) Frequency graph - CORRECT ANSWER - smooth curve, not necessarily
connecting all the points
contains the mode and pace
plot data point as the middle speed
Mode - CORRECT ANSWER - higher point on the percent frequency graph
point that occurs most often
most common speed that the vehicles were traveling
Pace - CORRECT ANSWER - 10mph range in which the most cars were found driving
not necessary +/-5 from the mode
calculated by using a straight edge to determine 10mph on the bottom axis and pull it up to touch
the sides of the graph
Percent Cumulative Frequency Graph - CORRECT ANSWER - cumulative frequency is
the percentage of cars traveling at and below the corresponding speed
contains the median, percentage of vehicles in pace, 85th percentile, 15th percentile, standard
deviation
plot data point as top speed in range
median - CORRECT ANSWER - aka 50th percentile
speed of cars traveling at or below the 50th percentile mark
percentage of vehicles in the pace - CORRECT ANSWER - difference between the
cumulative frequencies around the pace
*this is why we put the two graphs above each other
, 85th percentile and 15th percentile - CORRECT ANSWER - speed of cars traveling at or
below the 85/15th percentile mark
standard deviation (definiton) - CORRECT ANSWER - measures the dispersion of the
data
higher the standard deviation the higher the dispersion
standard deviation (formulas) - CORRECT ANSWER - same units as the x axis in the
graph
estimated formula: (85th percentile speed - 15th percentile speed) / 2
exact formula: (pictured), N = total number of data points, x-bar = mean (average) of all data
points, x = data point)
central tendency - CORRECT ANSWER - data that has this property is clustered around a
value
Dispersion - CORRECT ANSWER - aka spread in the data
voltage - CORRECT ANSWER - electrical potential difference between tow points in a
circuit
units: volts (V)
nodes - CORRECT ANSWER - area on a circuit between circuit elements
no potential difference across a node cause no circuit element is crossed
current - CORRECT ANSWER - flow of electrons through a circuit
created by a difference in electrical potential
flows from positive to negative