In statistics, the 68–95–99.7 rule, also known as the three-sigma rule or empirical rule, states that nearly all values lie within three standard deviations of the mean in a normal distribution.
About 68.27% of the values lie within one standard deviation of the mean. Similarly, about 95.45% of the values lie within two standard deviations of the mean. Nearly all (99.73%) of the values lie within three standard deviations of the mean.
In mathematical notation, these facts can be expressed as follows, where x is an observation from a normally distributed random variable, μ is the mean of the distribution, and σ is its standard deviation:
P( μ – σ ≤ x ≤ μ + σ ) ≈ 0.6827
P( μ –2σ ≤ x ≤ μ + 2σ ) ≈ 0.9545
P( μ –3σ ≤ x ≤ μ + 3σ ) ≈ 0.9973
So here A = μ – σ = 78.7 – 3.5 = 75.2 (answer
Answer:
52
Step-by-step explanation:
The split them up part is suppose to trick you, for there are still a total of 54 people cheering. So you do 54-2 since 2 people left and you have 52 still cheering.
Answer:
I cant see the whole thing But I think you're right
Answer:
D) 4.7
Step-by-step explanation:
this perpendicular connection with the circle center cuts this intersecting line in half, which is therefore on both sides of x 6.5 long.
I assume 16 is the diameter, so the radius is 8.
therefore, x is one side of the right-angled triangle of
radius
x
half of the intersecting line
Pythagoras
8² = x² + (6.5)²
64 = x² + 42.25
21.75 = x²
x = 4.7