Are you guys really smart?

(a + 3)(a - 2) whats the answer

const2013 [10]

(a+3)(a-2)

a^2-2a+3a-6

a^2+a-6

Answer is a^2+a-6

4 0

3 years ago

Read 2 more answers

A youth organization collected nickels and dimes for a charity drive. By the end of the 1-day drive, the youth had collected $63

uysha [10]

Let, the numbers of nickels be x.

Given, there were 5 times as many dimes as nickels.

So, the number of dimes = 5x

We know that 1 nickel = $(0.05)

So x nickels = $(0.05x)

Also we know that 1 dime = $(0.1)

So 5x dimes = $(0.1 ×5x) = $(0.5x)

Given total value of dimes and nickels at the end of day 1 is $63.80

So we can write the equation

$0.05x+0.5x = 63.80$

$0.55x = 63.80$

Now we to find x, we have to move 0.55 to the other side. As 0.55 is multiplied there so to move it we need to divide it to both sides.

$0.55x/0.55 = 63.80/0.55$

$x = 116$

So we have got the number of nickels = 116

Number of dimes = 5x = 5(116) = 580

So we have got the required answer.

Number of nickels = 116, number of dimes = 580.

8 0

3 years ago

The local farmer’s market sells a 4-pound basket of pears for $6.00. What is the price per pound?

Artyom0805 [142]

Answer:

1.50

Step-by-step explanation:

divide 6.00 by 4 and you get 1.5

5 0

3 years ago

The downtime per day for a computing facility has mean 4 hours and standard deviation .8 hour. Suppose that we want to compute p

xz_007 [3.2K]

Answer:

1

Step-by-step explanation:

Given :

Mean, μ = 4

Standard deviation, s = 0.8

Sample size, n = 30

The distribution is independent.

Z = (x - μ) / s /sqrt(n)

Probability that downtime period is between 1 and 5

P(1≤ x ≤ 5) :

[(x - μ) / (s /sqrt(n))] ≤ Z ≤ [(x - μ) / (s /sqrt(n))]

[(1 - 4) / (0.8 /sqrt(30))] ≤ Z ≤ [(5 - 4) / (0.8 /sqrt(30)]

[-3 / 0.1460593] ≤ Z ≤] 1 / 0.1460593]

P(-20.539602 ≤ Z ≤ 6.8465342)

P(Z ≤ 6.8465342) - P(Z ≤ - 20.5396)

P(Z ≤ 6.8465342) = 1 (Z probability calculator)

P(Z ≤ - 20.5396) = 0 (Z probability calculator)

1 - 0 = 1

3 0

3 years ago

A graduate student majoring in linguistics is interested in studying the number of students in her college who are bilingual. Of

Eddi Din [679]

Answer:

48.41% probability that 17 or fewer of them are bilingual.

Step-by-step explanation:

Binomial probability distribution

Probability of exactly x sucesses on n repeated trials, with p probability.

Can be approximated to a normal distribution, using the expected value and the standard deviation.

The expected value of the binomial distribution is:

$E(X) = np$

The standard deviation of the binomial distribution is:

$\sqrt{V(X)} = \sqrt{np(1-p)}$

Normal probability distribution

Problems of normally distributed samples can be solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

When we are approximating a binomial distribution to a normal one, we have that $\mu = E(X)$ , $\sigma = \sqrt{V(X)}$ .