Range is all positive real numbers
answer is D. last one
I hope this helps you
distance=speed×time
first cars time t
second cars time t+3
same distance
distance=55.t
distance=40. (t+3)
55t=40 (t+3)
55t-40t=120
15t=120
t=8
t+3=11
The answer is the mean.
"For a data set, the arithmetic mean, also called the mathematical expectation or average, is the central value of a discrete set of numbers: specifically, the sum of the values divided by the number of values."- Wikipedia
