Answer: in 95% of races, his finishing time will be between 62 and 64 seconds.
Step-by-step explanation:
The empirical rule states that for a normal distribution, nearly all of the data will fall within three standard deviations of the mean . The empirical rule is further illustrated below
68% of data falls within the first standard deviation from the mean.
95% fall within two standard deviations.
99.7% fall within three standard deviations.
From the information given, the mean is 63 seconds and the standard deviation is 5 seconds.
2 standard deviations = 2 × 0.5 = 1
63 - 1 = 62 seconds
63 + 1 = 64 seconds
Therefore, in 95% of races, his finishing time will be between 62 and 64 seconds.
Add them all up and divide 6 (the number of terms given). The answer is 9.66 or 9.7 rounded to the nearest tenth.
Hello from MrBillDoesMath!
Answer: infinite solutions
Discussion: I did a double take on this one but the left hand is
a + 3 + 2a = 3a +3
and the right hand side is
-1 + 3a + 4 = 3a + (4-1) = 3a + 3
The left and right sides of the equation are identical for all "a", i.e. for infinitely many "a" values.
Regards, MrB.
Look where the line is touching on the y-axis and that will be your y-value. From there or somewhere on the line use rise over run (rise/run, do not divide). Count how many times it goes up and then count how many times it goes left or right. Make sure to look where the line is going, up or down slanted. If the line is going down, but slanted it will be a negative slope; line going up and slanted is positive.