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3 years ago

5 of 8

Mathematics

1 answer:

aleksandr82 [10.1K]3 years ago

6 0

Given:

The mean age of 5 people in a room is 26 years.

A person enters the room. The mean age is now 33.

To find:

The age of the person who entered the room.

Solution:

Formula for mean:

$\text{Mean}=\dfrac{\text{Sum of observations}}{\text{Number of observations}}$

The mean age of 5 people in a room is 26 years.

$26=\dfrac{\text{Sum of ages of 5 people}}{5}$

$26\times 5=\text{Sum of ages of 5 people}$

$130=\text{Sum of ages of 5 people}$

The mean age is now 33. It means, the mean age of 6 people is 33.

$33=\dfrac{\text{Sum of ages of 6 people}}{6}$

$33\times 6=\text{Sum of ages of 6 people}$

$198=\text{Sum of ages of 6 people}$

Now, the age of the person who entered the room is

Required age = Sum of ages of 6 people - Sum of ages of 5 people

= $198-130$

= $68$

Therefore, the age of the person who entered the room is 68 years.

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The acceleration y, in meters per second squared, of an object after x seconds is given by y = 7 sin (pi/4 x). During the first

Nataly_w [17]

Answer: (0, 2) and (6, 10)

Step-by-step explanation:

The acceleration is:

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First, let's study the sin function:

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Sin(θ) decreases between pi/2 and (3/2)*pi.

And so on.

Here we have:

θ = x*(pi/2)

When x = 0, θ = 0.

And sin(θ) is increasing in θ = 0.

Then we must choose one of the options that start with x = 0.

now it will stop increasing when:

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x = 2.

So the acceleration is increasing in the segment (0,2)

And it will start increase again when:

θ = (3/2)*pi = x*(pi/4)

(3/2)*pi*(4/pi) = 6 = x.

So at x= 6 the acceleration starts increasing again, and the acceleration is only deffined until x = 10, then

the correct option is: (0, 2) and (6, 10)

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3 years ago

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3 years ago

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mylen [45]

Answer:

The value of annuity is $P_v = \$ 7929.9$

Step-by-step explanation:

From the question we are told that

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3 years ago

Write 7,004,000 in scientific notation.

MAXImum [283]

<span>7,004,000 in scientific notation.
=</span>7.004 x 10^6
as 7 is the first non zero digit
so decimal jumbed 6 numbers from right to left and exponent will be positive
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3 years ago