Variance of a continuous random variable X is defined as
Standard deviation is defined as

Hence standard deviation is the positive square root of variance.
You start with: (assuming x equals the cost to enter and y the cost of going on the rollercoasters.)
x+5y=35
x+11y=59. Multiply the top equation by -1, and subtract the equations, giving you -6y=-24, divide by -6 into both sides of the equation, to get y=4. Now replace y in one of the original equations (I recommend x+5y=35) and solve for x, giving you x=15
The cost for entering is 15 dollars, while each coaster is 4 dollars more. You could simplify this by changing y into x and making it slope-intercept form, to track your cost. y=4x+15, so it has a slope of 4, and a y-intercept of 15. This answer should give you a good grade on a test.
Answer:
$21.57
Step-by-step explanation:
4.5 (1.22) + 0.8 (1.70) + 4.6 (3.20) =
5.49 + 1.36 + 14.72
21.57
If Fabio drinks 2 quarts of water each day, he would drink 8 cups of water in accordance with direct proportion.
<h3>What is a proportion?</h3>
A proportion can be defined as an equation which is typically used to represent (indicate) the equality of two (2) ratios. This ultimately implies that, proportions can be used to establish that two (2) ratios are equivalent and solve for all unknown quantities.
Mathematically, a direct proportion can be represented by the following equation:
y = kx
Where:
- y and x are the variables.
- k represents the constant of proportionality.
By applying direct proportion, we have:
1 quarts = 4 cups
2 quarts = X cups
Cross-multiplying, we have:
X = 4 × 2
X = 8 cups.
In conclusion, the quantity of water which Fabio drinks each day is equal to 8 cups.
Read more on direct proportion here: brainly.com/question/1266676
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