Please please help .. Really need answer asap please and thank you

lukranit [14]

Answer: Distance traveled divided by rate provides the rate of change in position in time. For example, if Cole traveled 225 km at 45 km per hour and traveled 45/225 = 5 hours, then the rate of change in position was 30/5 = 20 minutes.

Step-by-step explanation:

7 0

3 years ago

Yesterday I drove 150 minutes at a speed of 100 miles/h. How many miles did I drve?

krok68 [10]

Answer: 250 miles

Step-by-step explanation:

I am not sure what grade level you are, but this is how it is done in college.

I hope it can give you an idea and be of some help.

First you have to convert 150 minutes to hours. Then you multiply your new hours to 100 miles.

150 minutes x <u> 1 hour </u> x<u> 100 miles </u>= 250 miles

60 mins. 1 hour

3 0

3 years ago

Use the following equation to find a line that is parallel: 10x + 3y - 4x = -24

Sati [7]

y=1/2x is your answer.

4 0

3 years ago

Population A and Population B both have a mean height of 70.0 inches with an SD of 6.0. A random sample of 50 people is picked f

Alex

Answer:

Sample mean from population A has probably more accurate estimate of its population mean than the sample mean from population B.

Step-by-step explanation:

To yield a more accurate estimate of the population mean, margin of error should be minimized.

margin of error (ME) of the mean can be calculated using the formula

ME= $\frac{z*s}{\sqrt{N} }$ where

z is the corresponding statistic in the given confidence level(z-score or t-score)

s is the standard deviation of the sample (or of the population if it is known)

N is the sample size

for a given confidence level, and the same standard deviation, as the sample size increases, margin of error decreases.

Thus, random sample of 50 people from population A, has smaller margin of error than the sample of 20 people from population B.

Therefore, sample mean from population A has probably more accurate estimate of its population mean than the sample mean from population B.

7 0

4 years ago

The population, P(t), of China, in billions, can be approximated by1 P(t)=1.394(1.006)t, where t is the number of years since th

vitfil [10]

Answer:

At the start of 2014, the population was growing at 8.34 million people per year.

At the start of 2015, the population was growing at 8.39 million people per year.

Step-by-step explanation:

To find how fast was the population growing at the start of 2014 and at the start of 2015 we need to take the derivative of the function with respect to t.

The derivative shows by how much the function (the population, in this case) is changing when the variable you're deriving with respect to (time) increases one unit (one year).

We know that the population, P(t), of China, in billions, can be approximated by $P(t)=1.394(1.006)^t$

To find the derivative you need to:

$\frac{d}{dt}\left(1.394\cdot \:1.006^t\right)=\\\\\mathrm{Take\:the\:constant\:out}:\quad \left(a\cdot f\right)'=a\cdot f\:'\\\\1.394\frac{d}{dt}\left(1.006^t\right)\\\\\mathrm{Apply\:the\:derivative\:exponent\:rule}:\quad \frac{d}{dx}\left(a^x\right)=a^x\ln \left(a\right)\\\\1.394\cdot \:1.006^t\ln \left(1.006\right)\\\\\frac{d}{dt}\left(1.394\cdot \:1.006^t\right)=(1.394\cdot \ln \left(1.006\right))\cdot 1.006^t$

To find the population growing at the start of 2014 we say t = 0

$P(t)' = (1.394\cdot \ln \left(1.006\right))\cdot 1.006^t\\P(0)' = (1.394\cdot \ln \left(1.006\right))\cdot 1.006^0\\P(0)' = 0.00833901 \:Billion/year$

To find the population growing at the start of 2015 we say t = 1

$P(t)' = (1.394\cdot \ln \left(1.006\right))\cdot 1.006^t\\P(1)' = (1.394\cdot \ln \left(1.006\right))\cdot 1.006^1\\P(1)' = 0.00838904 \:Billion/year$

To convert billion to million you multiple by 1000

$P(0)' = 0.00833901 \:Billion/year \cdot 1000 = 8.34 \:Million/year \\P(1)' = 0.00838904 \:Billion/year \cdot 1000 = 8.39 \:Million/year$

6 0

3 years ago