All categories

4 years ago

What is the value of b in the equation below?

Mathematics

2 answers:

grigory [225]4 years ago

8 0

Answer:

I think it is 4

Step-by-step explanation:

skelet666 [1.2K]4 years ago

6 0

Answer:

The last one 8

Step-by-step explanation:

You might be interested in

An experiment consists of rolling a standard six-sided die once. Event A is "rolling an even number" and event B is "rolling a 2

OleMash [197]

Answer:

(D)Events A and B are dependent, because P(B)≠P(B|A).

Step-by-step explanation:

<u>Definition:</u> Two events are independent if

$P(A)\cdot P(B)=P(B\cap A)\\$Equivalently:$\\P(B)=\frac{P(B\cap A)}{P(A)} \\P(B)=P(B|A)$

An experiment consists of rolling a standard six-sided die once.

Event A is "rolling an even number"

Even numbers are 2,4 and 6

$P(A)=3/6=1/2$

Event B is "rolling a 2."

P(B)=1/6

$\{A\cap B\}={2}\\P(A\cap B)=1/6$

Substitution into $P(B)=\frac{P(B\cap A)}{P(A)}$

Left Hand Side =1/6

Right Hand Side =(1/6)÷(1/2)=1/3

Since $P(B)\neq \frac{P(B\cap A)}{P(A)}$ , therefore $P(B)\neq P(B|A)$ which makes the events dependent.

7 0

4 years ago

There are 20 fasteners in each front door of a passenger car. There are 26 fasteners in each rear door. How many fasteners are t

Alik [6]

20 fasteners times 2= 40 for front door 26 fasteners times 2= 56 fasteners for rear doors 56+40=96

4 0

3 years ago

In Major League Baseball, the American League (AL) allows a designated hitter (DH) to bat in place of the pitcher, but in the Na

hammer [34]

Answer:

Step-by-step explanation:

From the given information:

Let:

$\mu_1$ represent the population mean no. for DH group.

$\mu_2$ represent the population mean no. for no DH group

$n_1$ represent the sample sizes of DH

$n_2$ represent the sample sizes of no DH

Sample size: $n_1 = n_2 = 20$

For both groups, the population standard deviation of runs scored = 2.54

i.e

$\sigma^2_1 = \sigma_2^2 = 2.54$

The null & alternative hypothesis;

$H_o : \mu_1 \le \mu_2 \\ \\ H_a: \mu_1 > \mu_2$

Level of significance:

The test statistics is:

$z = \dfrac{\bar x_1 - \bar x_2}{\sqrt{\dfrac{\sigma^2_1}{n_1} + \dfrac{\sigma_2^2}{n_2} }}$

where;

$\bar x_1$ = sample mean for DH group

$\implies \dfrac{1}{n_1} \sum \limit ^{n_1}_{i=1} x_1 \\ \\ = \dfrac{1}{20}(0+6+8+2+2+4+7+7+6+5+1+1+5+4+4+5+7+11+10+0) \\ \\ = \dfrac{92}{20}$

= 4.6

$\bar x_2$ = sample mean for no DH group

$\implies \dfrac{1}{n_2} \sum \limit ^{n_1}_{i=1} x_1 \\ \\ = \dfrac{1}{20}(3+6+2+4+0+5+7+6+1+8+12+4+6+3+4+0+5+2+1+4) \\ \\ = \dfrac{83}{20}$

= 4.15

Now:

$z = \dfrac{4.60- 4.15}{\sqrt{\dfrac{2.54^2}{20} + \dfrac{2.54^2}{20} }} \\ \\ = \dfrac{0.45}{\sqrt{0.32258 +0.32258 }} \\ \\ = \dfrac{0.45}{0.803219} \\ \\$

= 0.5602

Since the test is one-tailed by looking at that $H_a:$

The P-value = $P(Z > z)$

$\implies 1 - P(Z \le z) \\ \\ = 1 - P(Z \le 0.5602)$

Using Excel Function " =normdist(z)"; we have":

$= 1- 0.7123$

P-value = 0.2877

Decision rule: To reject $H_o$ , if $p-value < \alpha \ at \ 0.10$

Conclusion: SInce P = 0.2877 which is $> \ \alpha \ at \ 0.10.$

We fail to reject the $H_o$ and conclude that there is insufficient evidence to support the given claim that: $\text{more runs are scored in games for which DH is used.}$

8 0

3 years ago

reuben deposits $700 into an account that pays simple interest at a rate if 5% per year. How much interest will he be paid in th

ryzh [129]

Carmen deposits $400 into an account that plays simple interest at a rate of 5% per year. Amount in the account after 5 years:
$400 times (1.05)^5
=$510.51
The interest she will be paid in the first years = $110.51

3 0

4 years ago

Box A contains 7 items of which 2 are defective, and box B contains 6 items of which 1 is defective. If an item is drawn at rand

Katyanochek1 [597]

Answer:

P = 25/42

Step-by-step explanation:

We are asked to calculate the probability that if two items are selected from two different boxes, what is the probability that bought are non-defective.

In the first box A, the probability of selecting a non-defective item is 5/7

In the second box B, the probability of selecting a non-defective item is 5/6

Now the probability of selecting 2 items, one from each of the boxes and both are non-defective are as follows;

5/6 * 5/7 = 25/42

5 0

4 years ago