1 answer:
Answer:
(a + 2b)(a - b)
Step-by-step explanation:
Assuming you require the expression to be factored
Given
a² +
ab - b² ← factor out
from each term
= (a² + ab - 2b²) ← factor the quadratic
Consider the factors of the coefficient of the b² term(- 2) which sum to give the coefficient of the ab- term (+ 1)
The factors are + 2 and - 1, since
2 × - 1 = - 2 and 2 - 1 = + 1, thus
a² + ab - 2b² = (a + 2b)(a - b) and
a² +
ab - b² =
(a + 2b)(a - b)
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Answer:
Obese people
Lean People
Step-by-step explanation:
Previous concepts
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".
The empirical rule, also referred to as the three-sigma rule or 68-95-99.7 rule, is a statistical rule which states that for a normal distribution, "almost all data falls within three standard deviations (denoted by σ) of the mean (denoted by µ). Broken down, the empirical rule shows that 68% falls within the first standard deviation (µ ± σ), 95% within the first two standard deviations (µ ± 2σ), and 99.7% within the first three standard deviations (µ ± 3σ)".
Solution to the problem
Obese people
Let X the random variable that represent the minutes of a population (obese people), and for this case we know the distribution for X is given by:
Where and
On this case we know that 95% of the data values are within two deviation from the mean using the 68-95-99.7 rule so then we can find the limits liek this:
Lean People
Let X the random variable that represent the minutes of a population (lean people), and for this case we know the distribution for X is given by:
Where and
On this case we know that 95% of the data values are within two deviation from the mean using the 68-95-99.7 rule so then we can find the limits liek this:
The interval for the lean people is significantly higher than the interval for the obese people.