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3 years ago

10

A boat travelling upstream goes 36 kilometers in 6 hours. If the return trip takes only 3 hours, what is the speed (in kilometer

s per hour) of the boat in still water

1 answer:

mr_godi [17]3 years ago

8 0

11 kilometer per hour

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Suppose that 15% of the fields in a given agricultural area are infested with the sweet potato whitefly. One hundred fields in t

hram777 [196]

Answer:

a. $\mu=15$

b. $\mu=7.8586 \ and \ \mu=22.1414$

c. Choice A- Based on limits above, it is unlikely that we would see x = 45, so it might be possible that the trials are not independent.

Step-by-step explanation:

a.Binomial distribution is defined by the expression

$P(X=k)=C_k^n.p^k.(1-p)^{n-k}$

Let n be the number of trials, $n=100$

and p be the probability of success, $p=15\%$

The mean of a binomial distribution is the probability x sample size.

$\mu=np=100\times0.15=15$

b.Limits within which p is approximately 95%

sd of a binomial distribution is given as: $\sigma=\sqrt npq\\q=1-p$

Therefore, $\sigma=\sqrt(100\times0.015\times0.85)=3.5707$

Use the empirical rule to find the limits. From the rule, approximately 95% of the observations are within to standard deviations from mean.

$sd_1=>\mu-2\sigma=15-2\times3.3507=7.8586\\sd_2=>\mu-2\sigma=15+2\times3.3507=22.1414$

Hence, approximately 95% of the observations are within 7.8586 and 22.1414 (areas of infestation).

c. $x=45$ is not within the limits in b above (7.8586,22.1414). X=45 appears to be a large area of infestation. A.Based on limits above, it is unlikely that we would see x = 45, so it might be possible that the trials are not independent.

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3 years ago

A weight lifter does 9.8 J of work while lifting a weight straight upward through a distance of 0.12m. What was the force exerte

gulaghasi [49]

Answer:

The force exerted by the weight lifter is 81.7 N.

Step-by-step explanation:

We can find the force exerted by the weight lifter using the definition of work:

$W = F*d$ (1)

Where:

F: is the force

d: is the displacement

We have W = 9.8 J of work and d = 0.12 m, so by solving equation (1) for F we have:

$F = \frac{W}{d} = \frac{9.8 J}{0.12 m} = 81.7 N$

Therefore, the force exerted by the weight lifter is 81.7 N.

I hope it helps you!

3 0

2 years ago

Brad cuts a triangular prism with a plane parallel to the base of the prism what will the shape of the cross section be?

devlian [24]

the answer will be triangular/

Hope I helped. Mark as brainliest

4 0

3 years ago

Read 2 more answers

How many different ways are there to arrange the letters of the word PRISM?

Advocard [28]

Answer:

5! (5 factorial) or 120 ways

Step-by-step explanation:

You can arrange P different ways. R can be arranged only 4 different ways because Pwill be in one of the spots. Next, you can arrange "I" 3 different ways because P and R are already arranged in 2 spots, meaning you cant put "I" there. Next, S can be arranged in 2 different ways for the same reason. And lastly, M can only be arranged in 1 different way because the other spots are taken.

You can put it in any order. For example, M could be arranged 5 ways and P could be arranged in 1 way. You will still get 120 ways

Hopefully this helped. The explanation might be a bit confusing but I tried my best. I'm not good with explaining my solutions but I always try

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1 year ago

Determine the solution to each linear system by using the substitution method.

lana66690 [7]

A. 2x+3×5=34
2x+15=34
2×9.5=19
2×9.5+15=34

x=9.5

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2 years ago