ASAP what is the value of x

How do I solve this?

7nadin3 [17]

The minimum happens at x = -b/2a

x = -30 / 2(3) = -30/6 = -5

Now replace x in the equation with -5 and solve:

3(-5)^2 + 30(-5) +27 = 75 - 150 + 27 = -48

The minimum is at (-5,-48)

3 0

2 years ago

Read 2 more answers

A company services home air conditioners. It is known that times for service calls follow a normal distribution with a mean of 7

SCORPION-xisa [38]

Answer:

The probability that exactly eight of them take more than 93.6 minutes is 5.6015 $\times 10^{-6}$ .

Step-by-step explanation:

We are given that it is known that times for service calls follow a normal distribution with a mean of 75 minutes and a standard deviation of 15 minutes.

A random sample of twelve service calls is taken.

So, firstly we will find the probability that service calls take more than 93.6 minutes.

Let X = times for service calls.

So, X ~ Normal( $\mu=75,\sigma^{2} =15^{2}$ )

The z-score probability distribution for the normal distribution is given by;

Z = $\frac{X-\mu}{\sigma}$ ~ N(0,1)

where, $\mu$ = mean time = 75 minutes

$\sigma$ = standard deviation = 15 minutes

Now, the probability that service calls take more than 93.6 minutes is given by = P(X > 93.6 minutes)

P(X > 93.6 min) = P( $\frac{X-\mu}{\sigma}$ > $\frac{93.6-75}{15}$ ) = P(Z > 1.24) = 1 - P(Z $\leq$ 1.24)

= 1 - 0.8925 = 0.1075

The above probability is calculated by looking at the value of x = 1.24 in the z table which has an area of 0.8925.

Now, we will use the binomial distribution to find the probability that exactly eight of them take more than 93.6 minutes, that is;

$P(Y = y) = \binom{n}{r}\times p^{r} \times (1-p)^{n-r} ; y = 0,1,2,3,.........$

where, n = number of trials (samples) taken = 12 service calls

r = number of success = exactly 8

p = probability of success which in our question is probability that

it takes more than 93.6 minutes, i.e. p = 0.1075.

Let Y = Number of service calls which takes more than 93.6 minutes

So, Y ~ Binom(n = 12, p = 0.1075)

Now, the probability that exactly eight of them take more than 93.6 minutes is given by = P(Y = 8)

P(Y = 8) = $\binom{12}{8}\times 0.1075^{8} \times (1-0.1075)^{12-8}$

= $495 \times 0.1075^{8} \times 0.8925^{4}$

= 5.6015 $\times 10^{-6}$ .

6 0

2 years ago

What is 4/5 of 20? I thought it was 16 but apparently that was wrong??? I even looked it up

Simora [160]

Step-by-step explanation:

divided 20 by 5 times that by 4

20 divided by 5 is 4

4x4 is 16 its 16 you got it right

3 0

1 year ago

Read 2 more answers

Given a regular hexagon, find the measures of the angles formed by (a) two consecutive radii and (b)a radius and a side of the p

amid [387]

Notice the picture below

keep in mind, a regular hexagon, splits a circle in 6 equal angles

7 0

2 years ago

PLZ SOMEONE HELP ME I HAVE LESS THAN 20 MINUTES AND THIS IS THE QUESTION. SUBTRACT, MULTIPLY, DIVIDE, OR ADD, SIMPLIFY IN LOWEST

never [62]

Answer:

-n+24/4n

Step-by-step explanation:

-1/4+6/n

-n+24/4n

6 0

2 years ago