If x = -5 and y = 3 x − 5, then y equals what number?

If the train from Milan, Italy, to Rome, Italy, takes 6 hours at a speed of 130 miles per hour, how many miles from Milan is Rom

Fittoniya [83]

Step-by-step explanation:

the speed is 130 miles / hour.

that means the train travels 130 miles in 1 hour.

so, the question is, how far is it traveling. when it is going with that speed for 6 hours ?

well, 130 × 6 = 780 miles.

formally, speed is "distance / time".

multiplying this by some time, we have then an expression of "(distance / time) × time", which is then simply "distance".

8 0

2 years ago

Please help! Will mark brainliest! Simplify. <img src="https://tex.z-dn.net/?f=%283a%5E%7B2%7D%2A-3a%29" id="TexFormula1" ti

PilotLPTM [1.2K]

Step-by-step explanation:

Since -3a can be said to have a power of 1, we add the powers together and multiply the coefficients

-9a³

8 0

3 years ago

This graph shows the amount of charge left on my computer, c, after I have been awake for h hours.

timurjin [86]

Looks like 4.5. You want to find what h equals when c equals zero

6 0

3 years ago

Given that the measurement is in centimeters, find the area of the circle to the nearest tenth. (Use 3.14 for π)

coldgirl [10]

The area of a circle is equal to the radius squared times pie, basically:

${r}^{2} \times \pi$

The radius is 3, so we multiply 3 times 3 times pie to get the area.

You're gonna want to plug in the following into a calculator:

$3 \times 3 \times 3.14$

After getting 28.26 from such calculator, you need to round to the tenths place. In this number, the tenths place is the 2 next to the decimal on the right. Because the number after the 2 is a 6, that means we need to simplify the answer to (28.3). When you are rounding a number, you look at the number to the right, if it is 5 or bigger, add one and remove the rest, if it is less than 5, just get rid of the rest and leave it as it is.

5 0

3 years ago

Some parts of California are particularly earthquake-prone. Suppose that in one metropolitan area, 33% of all homeowners are ins

Lina20 [59]

Answer:

(a) The probability mass function of X is:

$P(X=x)={4\choose x}\ (0.33)^{x}\ (1-0.33)^{4-x};\ x=0,1,2,3...$

(b) The most likely value for X is 1.32.

(c) The probability that at least two of the four selected have earthquake insurance is 0.4015.

Step-by-step explanation:

The random variable X is defined as the number among the four homeowners who have earthquake insurance.

The probability that a homeowner has earthquake insurance is, p = 0.33.

The random sample of homeowners selected is, n = 4.

The event of a homeowner having an earthquake insurance is independent of the other three homeowners.

(a)

All the statements above clearly indicate that the random variable X follows a Binomial distribution with parameters n = 4 and p = 0.33.

The probability mass function of X is:

$P(X=x)={4\choose x}\ (0.33)^{x}\ (1-0.33)^{4-x};\ x=0,1,2,3...$

(b)

The most likely value of a random variable is the expected value.

The expected value of a Binomial random variable is:

$E(X)=np$

Compute the expected value of X as follows:

$E(X)=np$

$=4\times 0.33\\=1.32$

Thus, the most likely value for X is 1.32.

(c)

Compute the probability that at least two of the four selected have earthquake insurance as follows:

P (X ≥ 2) = 1 - P (X < 2)

= 1 - P (X = 0) - P (X = 1)

$=1-{4\choose 0}\ (0.33)^{0}\ (1-0.33)^{4-0}-{4\choose 1}\ (0.33)^{1}\ (1-0.33)^{4-1}\\\\=1-0.20151121-0.39700716\\\\=0.40148163\\\\\approx 0.4015$

Thus, the probability that at least two of the four selected have earthquake insurance is 0.4015.

3 0

3 years ago