Simplify (4x^-2 y^3)^3*2x^-4 y

18. A jar contains 200 coins.

dimaraw [331]

Answer:

Step-by-step explanation:

3 coins pulled are 10 cents or more

5 coins are under 10 cents

so 3 out of 8 coins are 10 cents or more

the jar contains 200 coins

This is a ratio problem 3 is to 8 as x (an unknown value) is to 200

3/8 = x/200 solve for x

times both sides by 200

200(3/8) = x solve directly here using a calculator

600/8 = x or keep similifying until you can divide more

300/4 = x easily I kept dividing the numerator and the

150/2 = x denominator by 2 until i got 150/2 = 75

75 = x

6 0

2 years ago

The rates of on-time flights for commercial jets are continuously tracked by the U.S. Department of Transportation. Recently, So

pshichka [43]

Answer:

There is a 32.22% probability that at least 3 flights arrive late.

Step-by-step explanation:

For each flight, there are only two possible outcomes. Either it arrives on time, or it arrives late. This means that we can solve this problem using binomial probability concepts.

Binomial probability distribution

The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

$P(X = x) = C_{n,x}.\pi^{x}.(1-\pi)^{n-x}$

In which $C_{n,x}$ is the number of different combinatios of x objects from a set of n elements, given by the following formula.

$C_{n,x} = \frac{n!}{x!(n-x)!}$

And $\pi$ is the probability of X happening.

In this problem, we have that:

There are 10 flights, so $n = 10$ .

A success in this case is a flight being late. 80% of its flights arriving on time, so 100%-80% = 20% arrive late. This means that $\pi = 0.2$ .

(a) Find the probability that at least 3 flights arrive late.

Either less than 3 flights arrive late, or at least 3 arrive late. The sum of these probabilities is decimal 1. This means that:

$P(X < 3) + P(X \geq 3) = 1$

$P(X \geq 3) = 1 - P(X < 3)$

In which

$P(X < 3) = P(X = 0) + P(X = 1) + P(X = 2)$

$P(X = x) = C_{n,x}.\pi^{x}.(1-\pi)^{n-x}$

$P(X = 0) = C_{10,0}.(0.2)^{0}.(0.8)^{10} = 0.1074$

$P(X = 1) = C_{10,1}.(0.2)^{1}.(0.8)^{9} = 0.2684$

$P(X = 2) = C_{10,2}.(0.2)^{2}.(0.8)^{8} = 0.3020$

So

$P(X < 3) = P(X = 0) + P(X = 1) + P(X = 2) = 0.1074 + 0.2684 + 0.3020 = 0.6778$

Finally

$P(X \geq 3) = 1 - P(X < 3) = 1 - 0.6778 = 0.3222$

There is a 32.22% probability that at least 3 flights arrive late.

3 0

3 years ago

3^3-2^2•(7-3)-45 <br><br> Someone please help !

Nata [24]

Answer:

-34 jjjjjjjjjjjjjjjjjjjjj

6 0

3 years ago

Ima houseseller earns a 3% commision for selling a house. if he sells a house for $120000, what is his commision

Masja [62]

Commission is earning a certain percentage of the total sold price.

To figure this out we need to find what is 3% of $120,000

We can do this by multiplying 3% and $120,000

First let's change 3% into a decimal.

3% = 0.03

Now lets multiply.

0.03 x $120,000 = $3,600

So this person earned $3,600 in commission.

Good Luck! :)

❤️ ❤️ ❤️

7 0

3 years ago

Help please

tester [92]

Answer:

64y² - 81

Step-by-step explanation:

(8y +9)(8y - 9)

64y² - 72y + 72y - 81

64y² - 81

6 0

3 years ago

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