Please help! 30 points! (it doens't say 30 points but it gives it to you after a second person answers)

The world brand of rivet placement is 11209 rivets in 9 hours and belongs to J. Mair of Ireland. If another person places 11209

Ilya [14]

Answer:

4.74 hours

Step-by-step explanation:

Given that both person have to place same number of rivets that is

11209

first person take 9 hours to complete the work

hence 1 hour work of 1st person is $\frac{1}{9}$ of total work

second person takes 10 hours to complete the same work

hence 1 hour work of 2nd person is $\frac{1}{10}$

Now if both work together then

1 hour work of both person = $\frac{1}{9} +\frac{1}{10}$ = $\frac{19}{90}$

thus working together they need $\frac{90}{19}$ hours = 4.74 hours to complete the whole work which is placing 11209 rivets

5 0

2 years ago

Which quantities in the advertisement represent a unit rate? 3 white shirts to 2 black shirts 2 black shirts for every 5 shirts

Finger [1]

Answer:

The Quantity 10$ per shirt represent a unit rate .

Step-by-step explanation:

Given:

There are 3 white shirts and 2 black shirts . per 10$ dollar.

To find:

Which quantities represent the unit rate ?

Solution:

Total of 5 shirts .

which means total of 50 dollar among 5 shirts.

i.e.50/5=10 dollars .

Hence each shirt causes 10 dollars or 10$ per shirt.

The Quantity 10$ per shirt represent a unit rate .

7 0

3 years ago

Read 2 more answers

Find the (a) mean, (b) median, (c) mode, and (d) midrange for the data and then (e) answer the given question. Listed below

mafiozo [28]

Answer:

a) $\bar X = 369.62$

b) $Median=175$

c) $Mode =450$

With a frequency of 4

d) $MidR= \frac{Max +Min}{2}= \frac{49+3000}{2}= 1524.5$

<u>e)</u> $s = 621.76$

And we can find the limits without any outliers using two deviations from the mean and we got:

$\bar X+2\sigma = 369.62 +2*621.76 = 1361$

And for this case we have two values above the upper limit so then we can conclude that 1500 and 3000 are potential outliers for this case

Step-by-step explanation:

We have the following data set given:

49 70 70 70 75 75 85 95 100 125 150 150 175 184 225 225 275 350 400 450 450 450 450 1500 3000

Part a

The mean can be calculated with this formula:

$\bar X = \frac{\sum_{i=1}^n X_i}{n}$

Replacing we got:

$\bar X = 369.62$

Part b

Since the sample size is n =25 we can calculate the median from the dataset ordered on increasing way. And for this case the median would be the value in the 13th position and we got:

$Median=175$

Part c

The mode is the most repeated value in the sample and for this case is:

$Mode =450$

With a frequency of 4

Part d

The midrange for this case is defined as:

$MidR= \frac{Max +Min}{2}= \frac{49+3000}{2}= 1524.5$

Part e

For this case we can calculate the deviation given by:

$s =\sqrt{\frac{\sum_{i=1}^n (X_i -\bar X)^2}{n-1}}$

And replacing we got:

$s = 621.76$

And we can find the limits without any outliers using two deviations from the mean and we got:

$\bar X+2\sigma = 369.62 +2*621.76 = 1361$

And for this case we have two values above the upper limit so then we can conclude that 1500 and 3000 are potential outliers for this case

5 0

2 years ago

Sean and his family are picking strawberries at a pick-your-own fruit farm. The rectangular strawberry field has an area of 210,

nasty-shy [4]

Answer:

512 ft is the length of the field

Step-by-step explanation:

Firstly, we need to know the area of the field. We have confirmed this to be rectangular. Since it’s a rectangular field, the area of the field can be obtained by multiplying the length of the field by the breadth or width of the field.

Mathematically A = L * W

In the question, A = 210,944 ft^2

L= ? and W = 412ft

In essence, we are trying to calculate the value for the length of the field

L = A/W

L = (210,944)/412 = 512ft

8 0

3 years ago

WILL GIVE BRAINLIEST!!! Given tan(theta) = 4/3 and pi < theta < (3pi)/2, find cos(2theta).

babymother [125]

Answer: $\cos 2 \theta = \dfrac{-7}{25}$

Step-by-step explanation:

Given: $\tan \theta = \dfrac{4}{3}$ and $\pi < \theta< \dfrac{3\pi }{2}$

To find: $\cos 2 \theta$

Now as we know

$\cos 2x = \dfrac{1- \tan ^2 x}{1+ \tan ^2 x}$

So we have

$\cos 2 \theta = \dfrac{1-(\dfrac{4}{3} )^2}{1+(\dfrac{4}{3} )^2} \\\\\Rightarrow \cos 2 \theta = \dfrac{1- \dfrac{16}{9} }{1+ \dfrac{16}{9} } = \dfrac{\dfrac{9-16}{9} }{\dfrac{9+16}{9}} = \dfrac{-7}{25}$

Therefore d. is the correct option

Hence , $\cos 2 \theta = \dfrac{-7}{25}$

3 0

3 years ago

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