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A tank that holds 6000 gallons of water may be filled by two pipes. One pipe pours water into the tank at the rate of 80 gallons

hammer [34]

Answer:

Below.

Step-by-step explanation:

Working together the rate is 80 + 120 = 200 gallons per minute.

(a) Time to fill tank = 6000 / 200 = 30 minutes.

(b) Let length of time the small pipe was used be x minutes , the the large pipe was used for is 60-x minutes.

Volume delivered by small pipe = y gallons, and by large pipe = 6000-y gallons.

Rate for small pipe = 80 = y/x.

Rate for large pipe = 120 = (6000-y) / 60-x.

y/x = 80

(6000-y) / 60-x = 120

From first equation y = 80x so:

6000 - 80 x = 7200 - 120x

40x = 1200

x = 30

So time for small pipe = 30 and time for large on = 30 minutes also.

C. In a similar way to part B:

y/x = 120

(6000-y) / 34 - x = 200

(6000-120x) / 34 - x = 200

6000 - 120x = 6800 - 200x

80x = 800 so the large pipe on its own took 10 minutes and the small pipe was used for 34 - 10 = 24 minutes.

3 0

3 years ago

The accounting department analyzes the variance of the weekly unit costs reported by two production departments. A sample of 16

dusya [7]

Answer:

$F=\frac{s^2_2}{s^2_1}=\frac{5.5}{2.5}=2.2$

Now we can calculate the p value but first we need to calculate the degrees of freedom for the statistic. For the numerator we have $n_2 -1 =16-1=15$ and for the denominator we have $n_1 -1 =16-1=15$ and the F statistic have 15 degrees of freedom for the numerator and 15 for the denominator. And the P value is given by:

$p_v =2*P(F_{15,15}>2.2)=0.138$

For this case the p value is highert than the significance level so we haev enough evidence to FAIL to reject the null hypothesis and we can conclude that the true deviations are not significantly different

Step-by-step explanation:

Information given

$n_1 = 16$ represent the sampe size 1

$n_2 =16$ represent the sample 2

$s^2_1 = 2.5$ represent the sample deviation for 1

$s^2_2 = 5.5$ represent the sample variance for 2

$\alpha=0.10$ represent the significance level provided

The statistic is given by:

$F=\frac{s^2_2}{s^2_1}$

Hypothesis to test

We want to test if the variations in terms of the variance are equal, so the system of hypothesis are:

H0: $\sigma^2_1 = \sigma^2_2$

H1: $\sigma^2_1 \neq \sigma^2_2$

The statistic is given by:

$F=\frac{s^2_2}{s^2_1}=\frac{5.5}{2.5}=2.2$

Now we can calculate the p value but first we need to calculate the degrees of freedom for the statistic. For the numerator we have $n_2 -1 =16-1=15$ and for the denominator we have $n_1 -1 =16-1=15$ and the F statistic have 15 degrees of freedom for the numerator and 15 for the denominator. And the P value is given by:

$p_v =2*P(F_{15,15}>2.2)=0.138$

For this case the p value is highert than the significance level so we haev enough evidence to FAIL to reject the null hypothesis and we can conclude that the true deviations are not significantly different

5 0

3 years ago

A pilot of a helicopter plans to release a bucket of water on a forest fire. The height y in feet of water t seconds after its r

frosja888 [35]

You’re gonna have to use the quadratic formula here and a bit of thinking. We know y is height, and once it touches the ground, it will be 0.

(-b +- sqrt b^2 - 4ac)/2a
2 +- sqrt(4 + 48(400))/-32
(2 +- 138.58)/-32
We don’t want a negative time because it’ll make no sense. So do subtraction

(2-138.58)/-32 = 4.27 seconds aka 4.3 seconds

4 0

3 years ago

Solve the following equations <br> 5^2x-2(5^x)-15=0

castortr0y [4]

Answer:

x = 1

Step-by-step explanation:

${5}^{2x} - 2( {5}^{x} ) - 15 = 0$