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romanna [79]
3 years ago
7

Abdul, while driving to school, computes the average speed for his trip to be 20 km/hr. On his return trip along the same route,

there is less traffic and the average speed is 40km/hr. What is the average sped for Abdul's trip?
Mathematics
1 answer:
gulaghasi [49]3 years ago
8 0
You need to find the total distance and the total time. The total distance is two times the distance to school, 2d.s=d/t=>t=d/sWhere s is speed, d is distance and t is time. So the time taken to get to school is:d/s1and the time taken to get back is:d/s2so the total time is:d/s1+d/s2=d(1/s1+1/s2)So, as speed = distance/time, divide the total distance by the total time:2d/d(1/s1+1/s2)=2/(1/s1+1/s2)=2/(1/20+1/40)=80/3≈26.7km/hr
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1/2 is half of a whole

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1/2 are numbers that can be simplify to halves= 1/2, 2/4, 3/6, 4/8, 5/10 and 1/2 are half of the denominator
4 0
3 years ago
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An insurance company states that it settles 85% of all life insurance claims within 30 days. A consumer group asks the state ins
BlackZzzverrR [31]

Using the z-distribution, it is found that since the p-value of the test is less than 0.05, we reject the null hypothesis and find that there is enough evidence to conclude that the true proportion of all life insurance claims made to this company that are settled within 30 days is less than 85%.

<h3>What are the hypothesis tested?</h3>

At the null hypothesis, it is tested if there is not enough evidence that the proportion is below 85%, that is:

H_0: p \geq 0.85

At the alternative hypothesis, it is tested if there is enough evidence that the proportion is below 85%, that is:

H_0: p < 0.85

<h3>What is the test statistic?</h3>

The test statistic is given by:

z = \frac{\overline{p} - p}{\sqrt{\frac{p(1-p)}{n}}}

In which:

  • \overline{p} is the sample proportion.
  • p is the proportion tested at the null hypothesis.
  • n is the sample size.

For this problem, the parameters are:

p = 0.85, n = 250, \overline{p} = \frac{203}{250} = 0.812

Hence the test statistic is:

z = \frac{\overline{p} - p}{\sqrt{\frac{p(1-p)}{n}}}

z = \frac{0.812 - 0.85}{\sqrt{\frac{0.85(0.15)}{250}}}

z = -1.68

<h3>What is the p-value and the conclusion</h3>

Using a z-distribution calculator, with a left-tailed test, as we are testing if the proportion is less than a value, and z = -1.68, the p-value is of 0.0465.

Since the p-value of the test is less than 0.05, we reject the null hypothesis and find that there is enough evidence to conclude that the true proportion of all life insurance claims made to this company that are settled within 30 days is less than 85%.

More can be learned about the z-distribution at brainly.com/question/16313918

#SPJ1

4 0
1 year ago
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Hunter-Best [27]

Answer:

$207.66

Step-by-step explanation:

349x.7=244.3

244.3x.85=207.665

Rounded to the nearest 100th

207.66

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3 years ago
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Hope this helps!

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I see so many people ask this. What does this mean?
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