All categories

3 years ago

I NEED HELPIM NO GOOD AT RATESI CANT GO ONE TILL THIS IS ANSWER

Mathematics

2 answers:

Murrr4er [49]3 years ago

8 0

Answer : The correct option is, (A) 7 hours 42 minutes

Explanation :

Average speed : It is defined as the ratio total distance to total time.

Formula used :

$\text{Average speed}=\frac{\text{Total distance}}{\text{Total time}}$

As per question,

Total distance traveled = 492.8 mile

Average speed = 64 mile/hour

Now put all the given values in the above formula, we get:

$\text{Average speed}=\frac{\text{Total distance}}{\text{Total time}}$

$64mile/hour=\frac{492.8mile}{\text{Total time}}$

$\text{Total time}=\frac{492.8mile}{64mile/hour}$

$\text{Total time}=7.7hour$

As we know that, 1 hour has 60 minutes.

7.7 hours

= 7 hr + 0.7 hr

= 7 hr + 0.7 × 60 min

= 7 hr + 42 min

$\text{Total time}=7\text{ hour }42\text{ minute}$

Therefore, the the take them to reach their destination will be, 7 hours 42 minutes.

goblinko [34]3 years ago

6 0

Answer:

I believe its d bc if you divide the distance by speed you get that

You might be interested in

Evaluate the limit with either L'Hôpital's rule or previously learned methods.lim Sin(x)- Tan(x)/ x^3x → 0

Vsevolod [243]

Answer:

$\dfrac{-1}{6}$

Step-by-step explanation:

Given the limit of a function expressed as $\lim_{ x\to \ 0} \dfrac{sin(x)-tan(x)}{x^3}$ , to evaluate the following steps must be carried out.

Step 1: substitute x = 0 into the function

$= \dfrac{sin(0)-tan(0)}{0^3}\\= \frac{0}{0} (indeterminate)$

Step 2: Apply L'Hôpital's rule, by differentiating the numerator and denominator of the function

$= \lim_{ x\to \ 0} \dfrac{\frac{d}{dx}[ sin(x)-tan(x)]}{\frac{d}{dx} (x^3)}\\= \lim_{ x\to \ 0} \dfrac{cos(x)-sec^2(x)}{3x^2}\\$

Step 3: substitute x = 0 into the resulting function

$= \dfrac{cos(0)-sec^2(0)}{3(0)^2}\\= \frac{1-1}{0}\\= \frac{0}{0} (ind)$

Step 4: Apply L'Hôpital's rule, by differentiating the numerator and denominator of the resulting function in step 2

$= \lim_{ x\to \ 0} \dfrac{\frac{d}{dx}[ cos(x)-sec^2(x)]}{\frac{d}{dx} (3x^2)}\\= \lim_{ x\to \ 0} \dfrac{-sin(x)-2sec^2(x)tan(x)}{6x}\\$

$= \dfrac{-sin(0)-2sec^2(0)tan(0)}{6(0)}\\= \frac{0}{0} (ind)$

Step 6: Apply L'Hôpital's rule, by differentiating the numerator and denominator of the resulting function in step 4

$= \lim_{ x\to \ 0} \dfrac{\frac{d}{dx}[ -sin(x)-2sec^2(x)tan(x)]}{\frac{d}{dx} (6x)}\\= \lim_{ x\to \ 0} \dfrac{[ -cos(x)-2(sec^2(x)sec^2(x)+2sec^2(x)tan(x)tan(x)]}{6}\\\\= \lim_{ x\to \ 0} \dfrac{[ -cos(x)-2(sec^4(x)+2sec^2(x)tan^2(x)]}{6}\\$

Step 7: substitute x = 0 into the resulting function in step 6

$= \dfrac{[ -cos(0)-2(sec^4(0)+2sec^2(0)tan^2(0)]}{6}\\\\= \dfrac{-1-2(0)}{6} \\= \dfrac{-1}{6}$

Hence the limit of the function $\lim_{ x\to \ 0} \dfrac{sin(x)-tan(x)}{x^3} \ is \ \dfrac{-1}{6}$ .

3 0

3 years ago

Two buildings are 12m apart on the same horizontal level. From the top of the taller building, the angle of depression of the bo

Ksenya-84 [330]

Answer:

4.61 m

Step-by-step explanation:

The angle of depression of the bottom of the shorter building from the top of the taller building = 48° equals the angle of elevation of the top of the taller building from the bottom of the shorter building

Using trig ratios

tan48° = H/d where H = height of taller building and d = their distance apart = 12 m

H = dtan48° = 12tan48° = 13.33 m

Also, the angle of elevation of the top of the shorter building from the bottom of the taller building is 36°

Using trig ratios

tan36° = h/d where h = height of shorter building

h =dtan36° = 12tan36° = 8.72 m

Now, the difference in height of the buildings is thus H - h = 13.33 m - 8.72 m = 4.61 m

4 0

3 years ago

Suppose that scores on a knowledge test are normally distributed with a mean of 60 and a standard deviation of 4.3. Scores on an

Sphinxa [80]

Question:

(c) Boris also took a logic test. His z-score on that test was +0.93 . Does this change the answer to which test Boris performed better on? Explain your answer using z-scores.

Answer:

The answers to the questions are;

(a) Based on the z score, Boris perform better on his aptitude test.

(b) Based on the z score, Callie perform better on his knowledge test .

Yes as Boris now performed best on the logic test.

Step-by-step explanation:

The z-score of a score is a measurement of the score withe respect to its distance from the mean as a factor of the standard deviation.

To solve the question, we note that we are required to find the z score as follows.

z score is given by $z = \frac{x -\mu}{\sigma}$

Where:

z = Standard score

x = Score

σ = Standard deviation

μ = Mean

(a) To find out which test did Boris performed better usin z score, we have

Boris scored a

57 on the knowledge test and

106 on the aptitude test

Therefore the z sore for the knowledge test is

$z = \frac{x -\mu}{\sigma}$

Here

x = 57

μ = 60

σ = 4.3

Therefore

$z_{knowledge} = \frac{57 -60}{4.3}$ = -3/4.3 = -30/43 = -0.6977

The z sore for Boris on the aptitude test is

Here

x = 106

μ = 110

σ = 7.1

$z_{aptitude} = \frac{106 -110}{7.1}$ = -40/17 = -0.5634

Based on the z score, Boris perform better on the aptitude test as his z score is higher (on the number line), --0.5634, compared to the z score on the knowledge test , -0.6977

(b) For Callie we have

Callie scored a

63 on the knowledge test and

114 on the aptitude test

Therefore the z sore for the knowledge test is

$z = \frac{x -\mu}{\sigma}$

Here

x = 63

μ = 60

σ = 4.3

Therefore

$z_{knowledge} = \frac{63 -60}{4.3}$ = 3/4.3 = 30/43 = 0.6977

The z sore for Callie on the aptitude test is

Here

x = 114

μ = 110

σ = 7.1

$z_{aptitude} = \frac{114 -110}{7.1}$ = 40/17 = 0.5634

Based on the z score, Callie perform better on the knowledge test as his z score is higher (on the number line), 0.6977, compared to the z score on the aptitude test , 0.5634.

$z_{aptitude}$ = - 0.5634 then

$z_{logic}$ > $z_{knowledge}$ > $z_{aptitude}$

Therefore Boris now performed best on the logic test.

6 0

2 years ago

Which of the decimal value given below is the largest? 0.52 0.052 0.0052

professor190 [17]

0.52 because 52/100 is better than 52/1000 and 52/10000

5 0

3 years ago

Some one help me please

levacccp [35]

I think the answer is 6t=9

7 0

2 years ago