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3 years ago

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Mathematics

1 answer:

andriy [413]3 years ago

7 0

I’m sorry I don’t get it

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Original price :$91.25, Tax:5.4%, Final price?

Cloud [144]

The final price is $96.18

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3 years ago

Read 2 more answers

Substitute x with 2.

Marina CMI [18]

Answer: -5

Step-by-step explanation:

13-4(2) / 2(2)^2-7(2)+5

5 / -1

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3 years ago

HELP!!! MARKING BRANLIEST!!!! MATH SUCKS!!!!!

iren2701 [21]

The second option! just did that not too long ago

4 0

3 years ago

Read 2 more answers

The product of three consecutive numbers is 990. What is the sum you f the 3 whole numbers?

Amanda [17]

Answer:

Step-by-step explanation:

If the three numbers are x, x+1, and x+2, then:

x (x+1) (x+2) = 990

x (x² + 3x + 2) = 990

x³ + 3x² + 2x - 990 = 0

(x - 9) (x² + 12x + 110) = 0

Since x must be a whole number, x = 9. You can also use simple trial and error to find that the three numbers are 9, 10, 11.

The sum is:

9 + 10 + 11 = 20

4 0

4 years ago

Results of a survey conducted in 15 large cities within the U.S. finds that the average commute time one way to/from work is 25.

irina1246 [14]

Answer:

We conclude that commute time in her city is less than the amount reported by the survey which is 25.4 minutes.

Step-by-step explanation:

We are given the following in the question:

Population mean, μ = 25.4 minutes

Sample mean, $\bar{x}$ = 22.1 minutes

Sample size, n = 15

Alpha, α = 0.10

Sample standard deviation, s = 5.3 minutes

First, we design the null and the alternate hypothesis

$H_{0}: \mu = 25.4\text{ minutes}\\H_A: \mu < 25.4\text{ minutes}$

We use one-tailed t(left) test to perform this hypothesis.

Formula:

$t_{stat} = \displaystyle\frac{\bar{x} - \mu}{\frac{s}{\sqrt{n}} }$

Putting all the values, we have

$t_{stat} = \displaystyle\frac{22.1 - 25.4}{\frac{5.3}{\sqrt{15}} } = -2.411$

Now, $t_{critical} \text{ at 0.10 level of significance, 14 degree of freedom } = -1.345$

Since,

$t_{stat} < t_{critical}$

We fail to accept the null hypothesis and reject it. We accept the alternate hypothesis.

Thus, there is enough evidence to conclude that commute time in her city is less than the amount reported by the survey which is 25.4 minutes.

7 0

4 years ago