PLEASE HELP URGENT WILL MARK BRAINIEST

BartSMP [9]

The answer is A if I am correct

3 0

2 years ago

working together, shawn and hector can install a tile floor in 6 hours. it would take shawn 9 hours to do the job alone. what is

Vikki [24]

First, let x be the number of hours it will take for Hector to finish the same job alone. This means that every hour, Hector can do 1/x of the job. The amount of work done by Shawn and Hector in 6 hours should be equal to 1 complete work. This can be expressed as,
(1/9 + 1/x)(6) = 1
The value of x is 18. Thus, Hector can to 1/18 of the job in one hour.

8 0

3 years ago

Read 2 more answers

Which are the following statements is 6×7 = 42

Alex787 [66]

Answer:

A and B are both correct

Step-by-step explanation:

the definitions of the following words are:

factor- a number or quantity that when multiplied with another produces a given number or expression.

multiple- a number that can be divided by another number without a remainder.

6 multiplied with 7 equals 42

42 divided by 7 equals 6

another way of phrasing it:

7 and 6 are factors of 42

and

42 is a multiple of both 7 and 6

hope this helped!

8 0

3 years ago

The service life of a battery used in a cardiac pacemaker is assumed to be normally distributed. A random sample of ten batterie

Fittoniya [83]

Answer:

The confidence interval is $25.16 < \mu < 26.85$

Step-by-step explanation:

From the question we are given a data set

25.5, 26.1, 26.8, 23.2, 24.2, 28.4, 25.0, 27.8, 27.3, and 25.7.

The mean of the this sample data is

$\= x = \frac{\sum x_i}{n}$

where is the sample size with values n = 10

$\= x = \frac{25.5+ 26.1+ 26.8+23.2+ 24.2+ 28.4+ 25.0+ 27.8+ 27.3+ 25.7}{10}$

$\= x = 26$

The standard deviation is evaluated as

$\sigma = \sqrt{\frac{\sum (x-\= x)}{n} }$

substituting values

$= \sqrt{\frac{ ( 25.5-26)^2, (26.1-26)^2, (26.8-26)^2, (23.2-26)^2}{10} }$

$\cdot \ \cdot \ \cdot \sqrt{\frac{ ( 24.2-26)^2, (28.4-26)^2+( 25.0-26)^2+ (27.8-26)^2+( 27.3-26)^2+( 25.7-26)^2}{10} }$

$\sigma = 1.625$

The confidence level is given as 90% hence the level of significance is calculated as

$\alpha = 100 -90$

$\alpha =10$ %

$\alpha = 0.10$

Now the critical values of $\frac{\alpha }{2}$ is obtained from the normal distribution table as

$Z_{\frac{\alpha }{2} } = 1.645$

The reason we are obtaining the critical values of $\frac{\alpha }{2}$ instead of $\alpha$ is because we are considering two tails of the area under the normal curve