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3 years ago

The mean of 40 observations was 160. It was detected on rechecking that the salue of

Mathematics

1 answer:

Ierofanga [76]3 years ago

7 0

Answer: The correct mean is 161.

Step-by-step explanation: The question states that we have computed the mean of 40 observations and the mean is 160. This means the set of data altogether is 40 numbers. In order to arrive at the mean, we must have added all 40 observed data to get the summation of observed data and divided this by 40. In other words, we must have done something like,

Mean = {Summation} x/{x}

Where x = 40 and the mean computed is 160.

Therefore,

160 = {summation}x/40

By cross multiplication we now have

160 (40) = {summation} x

6400 = {summation}x.

However, we must not forget that one of the values in the observed data was wrongly copied as 125, (instead of 165). What this means is that the summation of all observed data is having a shortage of 40 (that is, 165 - 125). If we now insert the correct figure of 165 in place of the wrong one which is 125, our summation of observed data would now become 6440 (the shortage of 40 would have been added back to 6400).

What we now have is

Mean = {summation}x/x

Mean = 6440/40

Mean = 161

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3 years ago

Between which pair of numbers is the exact product of 379 and 8.

artcher [175]

So many answers possible.

Let us take, by numbers they mean integers.

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4 years ago

Read 2 more answers

A parallelogram has an area of 160 square meters and a height of 4 meters. What is the length of the base of the parallelogram?

Simora [160]

The length of the base is 40 meters

<h3>How to determine the length of the base?</h3>

We have:

Area= 160 square meters

Height = 4 meters

The area is calculated using:

Area = Base * Height

So, we have:

160 = Base * 4

Divide both sides by 4

Base = 40

Hence, the length of the base is 40 meters

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brainly.com/question/24487155

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2 years ago

Suppose the interval [negative 2,0] is partitioned into nequals4 subintervals. What is the subinterval length Upper Delta x?

Maslowich

Answer:

We find the length of each subinterval dividing the distance between the endpoints of the interval by the quantity of subintervals that we want.

Then

Δx= $\frac{0-(-2)}{4}=\frac{2}{4}=\frac{1}{2}$

Now, each $x_i$ is found by adding Δx iteratively from the left end of the interval.

$x_0=-2\\x_1=-2+\frac{1}{2}=\frac{-3}{2}\\x_2=\frac{-3}{2}+\frac{1}{2}=-1\\x_3=-1+\frac{1}{2}=-\frac{1}{2}\\x_4=\frac{-1}{2}+\frac{1}{2}=0$

Each subinterval is

$s_1=[-2,-3/2]\\s_2=[-3/2,-1]\\s_3=[-1,-1/2]\\s_4=[-1/2,0]$

The midpoints of the subintervals are

$m_1=\frac{-2-3/2}{2}=\frac{-7/2}{2}=\frac{-7}{4}\\m_2=\frac{-1-3/2}{2}=\frac{-5/2}{2}=\frac{-5}{4}\\m_3=\frac{-1/2-1}{2}=\frac{-3/2}{2}=\frac{-3}{4}\\m_4=\frac{0-1/2}{2}=\frac{-1}{4}$