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
68.04 grams
Since it's half a pound you would need to find thirty percent of half a pound
Answer: The penguin will walk 75.15 feet in 45 sec
The 1st option is correct.
Answer: x = -4
Step-by-step explanation:
1/2 * (x - (-6)) = 1
distribute
1/2x + 3 = 1
isolate the variable
1/2x = -2
x = - 4