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3 years ago

Speed, Velocity or Acceleration?

SAT

1 answer:

qaws [65]3 years ago

5 0

Answer:

Acceleration

Explanation:

Speed is how fast something moves.

Velocity is how fast it moves and in what direction it moves in.

Acceleration is the change in how fast it moves. I.e. if it speed up or slows down.

Here we are not given a speed, but are told that the subway car slows down (a negative change in speed), which is a change in speed, therefore it is acceleration (or more accurately deceleration as it is negative acceleration, slowing down, but acceleration is usually used to describe both.)

Hope this helped!

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The rise of nativism towards the end of the 1800's lead to what?.

miskamm [114]

Hello! An answer I can give you is the “Chinese exclusion Act”
This act was published May of 1882 and repealed December of 1943.

3 0

3 years ago

company manufactured six television sets on a given day, and these TV sets were inspected for being good or defective. The resul

lana [24]

Sampling distribution involves the proportions of a data element in a given sample.

The proportion of Good TV set is 0.67
The number of ways of selecting 5 from 6 TV sets is 6
The number of ways of selecting 4 from 6 TV sets is 15

Given

$n = 6$

Sample Space = Good, Good, Defective, Defective, Good, Good

(a) Proportion that are good

From the sample space, we have:

$Good = 4$

So, the proportion (p) that are good are:

$p = \frac{Good}{n}$

$p = \frac{4}{6}$

$p = 0.67$

(b) Ways to select 5 samples (without replacement)

This is calculated using:

$^nC_r = \frac{n!}{(n - r)!r!}$

Where

$r = 5$

So, we have:

$^6C_5 = \frac{6!}{(6 - 5)!5!}$

$^6C_5 = \frac{6!}{1!5!}$

$^6C_5 = \frac{6 \times 5!}{1 \times 5!}$

$^6C_5 = \frac{6}{1}$

$^6C_5 = 6$

Hence, there are 6 ways

(c) All possible sample space of 4

First, we calculate the number of ways to select 4.

This is calculated using:

$^nC_r = \frac{n!}{(n - r)!r!}$

Where

$r = 4$

So, we have:

$^6C_4 = \frac{6!}{(6 - 4)!4!}$

$^6C_4 = \frac{6!}{2!4!}$

$^6C_4 = \frac{6 \times 5 \times 4}{2 \times 1 \times 4!}$

$^6C_4 = \frac{30}{2}$

$^6C_4 = 15$

So, the table is as follows:

$\left[\begin{array}{ccc}TV&Good&Proportion\\1,2,3,4&2&0.5&2,3,4,5&2&0.5&3,4,5,6&2&0.5\\4,5,6,1&3&0.75&5,6,1,2&4&1&6,1,2,3&3&0.75\\1,2,3,5&3&0.75&3,5,6,2&3&0.75&1,3,4,5&2&0.5\\1,3,4,6&2&0.5&1,4,5,2&3&0.75&2,4,6,1&3&0.75\\2,4,6,3&2&0.5&2,4,6,5&3&0.75&3,5,6,1&3&0.75\end{array}\right]$

The proportion column is calculated by dividing the number of Good TVs by the total selected (4) i.e.

$p = \frac{Good}{n}$

(d) The sampling distribution

In (a), we have:

$p = 0.67$ --- proportion of Good TV

The sampling error is calculated as follows:

$SE_n = |p - p_n|$

So, we have:

$\left[\begin{array}{ccc}TV&Good&SE\\1,2,3,4&2&0.17&2,3,4,5&2&0.17&3,4,5,6&2&0.17\\4,5,6,1&3&0.08&5,6,1,2&4&0.33&6,1,2,3&3&0.08\\1,2,3,5&3&0.08&3,5,6,2&3&0.08&1,3,4,5&2&0.17\\1,3,4,6&2&0.17&1,4,5,2&3&0.08&2,4,6,1&3&0.08\\2,4,6,3&2&0.17&2,4,6,5&3&0.08&3,5,6,1&3&0.08\end{array}\right]$