What is the size of the sample space for flipping 7 coins? Write your answer as a single integer.

A rectangular bird sanctuary is being created with one side along a straight riverbank. the remaining three sides are to be encl

Mariana [72]

<span>2 km wide by 4 km long with the long side parallel to the river. So we can enclose a rectangular area using just 3 sides since the 4th side is provided free by the river. I'll use the variable L to represent the length of the side that's parallel to the river and W to represent the distance from the river that parallel side is. So the total perimeter of the fence will be 2W + L. Let's write down some equations. Area enclosed A = W * L Length of L expressed in terms of W 8 = 2W + L 8 - 2W = L Now substitute (8-2W) for L in the equation for the area. A = W * L A = W * (8-2W) A = 8W - 2W^2 Since we're looking for a maximum value, that will happen when the slope of the function is equal to 0. And the first derivative of the function tells you the slope at each point. So we need to calculate the first derivative. For simple functions such as what we have, we just need to multiply the coefficient of each term by the exponent of that term, then subtract 1 from the exponent. So let's calculate the first derivative of A = 8W - 2W^2 A = 8W - 2W^2 The term 8W has an implied exponent of 1 for W, so 8 * 1 = 8. And 1 - 1 = 0. So we have 8W^0. And since W^0 = 1, we have 8 as the 1st term of the derivative. The next term is -2W^2. So -2*2 = -4 and 2-1 = 1, giving us -4W^1. And we can get rid of the explicit exponent of 1 since that's assumed to exist giving us a term of -4W. So the first derivative becomes A' = 8 - 4W Now let's solve that equation for A' = 0. A' = 8 - 4W 0 = 8 - 4W 4W = 8 W = 2 So the ideal width of the fence is 2. And looking back at the equation 8 - 2W = L, we can calculate the length as 8 - 2*2 = 8 - 4 = 4, so the length of the fence is 4. So the dimensions of the sanctuary is 4 km parallel to the river and extended 2 km from the river for a total area of 4*2 = 8 km^2. To demonstrate that is the ideal size, let's show that if the width is either smaller or larger, then we'll have a smaller sanctuary. Let's show the smaller case. For this we'll introduce a variable called "e" which represents a very tiny, but non-zero amount of length. So we'll call the width W+e or 2+e and the length will be 8 - 2*(2+e) = 8 - 4 - 2e = 4 - 2e So the area is A = WL A = (2+e)(4-2e) A = 8 -4e + 4e - 2e^2 A = 8 - 2e^2 And as you can see, as long as e is none zero the area will be smaller than 8 km^2. Now let's try a width that's less than 2 by a tiny amount. Our width is now (2-e) and that makes our length (4+2e). So A = WL A = (2-e)(4+2e) A = 8 + 4e -4e - 2e^2 A = 8 - 2e^2 And once again, if the width is slightly smaller so the length is slightly longer, the area is once again, slightly smaller. So the absolute best side for the sanctuary is 2 km wide by 4 km long.</span>

6 0

4 years ago

What is the product in lowest terms?

Alisiya [41]

-5/12 × 8/13

First, we need to start out by applying the multiplication rule towards fractions. If you haven't learned or don't remember the rules, you can always look up fraction rules. The rule is: a/b × c/d = ac/bd. Basically, we are combining the numerators and both of the denominators.
$- \frac{5 \times 8}{12 \times 13}$

Second, let's now multiply what we have in the fraction. (5 × 8 = 40) and (12 × 13 = 156). Doing so will create a new fraction for us to use.
$-\frac{40}{156}$

Third, now obviously, we can simplify the fraction we just got into lower terms. To do that, we have to collect the greatest common factor (GCF) of both the numerator and denominator and list their factors to find the common factor that is the greatest.

Factors of 40: 1, 2, 4, 5, 8, 10, 20, 40
Factors of 156: 1, 2, 3, 4, 6, 12, 13, 26, 39, 52, 78, 156

Out of the listed factors, which of those are the common ones? 1, 2, and 4 are the common factors. Since we are looking for the greatest common factor, it would be 4 since that is the higher number out of the commons. The GCF is 4.

Fourth, we can now divide our numerator (40) and our denominator (156) by the GCF we just found out, which was 4.
$40 \div 4 = 10 \\ 156 \div 4 = 39$

Fifth, our last step is to create our new simplified fraction. All we have to do is take our new numerator and denominator to see the fraction.

Answer in fraction form: $\fbox {-10/39}$
Answer in decimal form: $\fbox {-0.2564}$

4 0

3 years ago

ASAP Please!!<br><br>What is 25((-5/2)x+(1/2))?

Tresset [83]

Use the distributive property of multiplication.
25(-5x/2)=-62.5x, and 25(1/2)=12.5.
Add these together: -62.5x + 12.5 (answer)

7 0

3 years ago

What is 10984 rounded to the nearest 10 thousand?

Gelneren [198K]

10984 rounded to the nearest thousand is 11,000

3 0

3 years ago

What had the biggest effect on the earths orbit about the sun , explain.

andreev551 [17]

Answer:

The Earth's orbit makes a circle around the sun. At the same time the earth orbits around the sun, it also spins. In science, we cal that rotating on its axis. Since the earth orbits the sun AND rotates on its axis at the same time we experience seasons, day and night, and changing shadows throughout the day.

8 0

3 years ago