Another one i need help with

Identify the terms ,like terms ,coefficients,and constants in 7-5x+1

777dan777 [17]

Constants: -5x
like terms: 7, 1
terms: 1, 7, -5x
coeffcients: 5

7 0

3 years ago

A random sample of 49 statistics examinations was taken. the average score, in the sample, was 84 with a variance of 12.25. the

tester [92]

Since in this case we are only using the variance of the sample and not the variance of the real population, therefore we use the t statistic. The formula for the confidence interval is:

CI = X ± t * s / sqrt(n) ---> 1

Where,

X = the sample mean = 84

t = the t score which is obtained in the standard distribution tables at 95% confidence level

s = sample variance = 12.25

n = number of samples = 49

From the table at 95% confidence interval and degrees of freedom of 48 (DOF = n -1), the value of t is around:

t = 1.68

Therefore substituting the given values to equation 1:

CI = 84 ± 1.68 * 12.25 / sqrt(49)

CI = 84 ± 2.94

CI = 81.06, 86.94

Therefore at 95% confidence level, the scores is from 81 to 87.

6 0

3 years ago

Find the number of ways of arranging the numbers

Doss [256]

First of all, note that all integers are either 0,1, or 2 modulo 3 (if you're not familiar with this terminology, it means that every integer is either a multiple of 3, or it is 1 or 2 away from a multiple of 3).

So, we can think of our numbers as

$\begin{array}{c|c}x&x\mod 3\\0&0\\1&1\\2&2\\3&0\\4&1\\5&2\\6&0\\7&1\\8&2\\9&0\end{array}$

In order to make sure that the sum of any three adjacent numbers is divisible by 3, we have to make sure that any group of 3 three adjacent numbers contains a 0, a 1 and a 2. This is possible only if we arrange our 9 numbers in 3 groups of 3 numbers containing 0,1 and 2 exactly once, repeating always the same pattern.

For example, we could arrange our numbers following the pattern

$0,1,2,0,1,2,0,1,2$

or

$2,0,1,2,0,1,2,0,1$

We have $3!=6$ possible patterns. Suppose for example that we choose the pattern

$0,1,2,0,1,2,0,1,2$

One possible way of following this pattern would be the arrangement

$3,1,2,6,4,5,9,7,8$

In fact, we substituted every '0' with a multiple of 3 (3, 6 or 9), every '1' with a number 1 away from a multiple of 3 (1, 4 or 7) and every '2' with a number 2 away from a multiple of 3 (2, 5 or 8).

This means that, once we fix a patter, we have 3 choices for the first 3 slots, 2 choices for the next 3 slots, and the final slot will be fixed. So, we have

$3\cdot 3\cdot 3\cdot 2 \cdot 2 \cdot 2 = 216$

possible ways of following a fixed pattern. Since the number of patterns was 6, we have

$216\cdot 6 = 1296$

possible arrangements.

7 0

3 years ago

Read 2 more answers

Question 12 onlyyyyyyyy

netineya [11]

For number 12 you need to make an expression using the information given. a) 25g + 18r + 15b could be the expression.
b) The variables would be 25g for the 25 gold seats, 18r for the 18 red seats and 15b for the 15 blue seats.
c) Plug in the number given according to the variables.
25(100) + 18(250) + 15(200)
2500 + 4500 + 3000
7000 + 3000
$10,000

5 0

3 years ago

A projectile was launched straight up from the ground with an initial velocity of 48 ft/s. The height of the projectile t second

alex41 [277]

Factor f(t) and you can identify the values of t for which the height is zero.
.. f(t) = -16t(t -3)

The projectile lands after 3 seconds in the air. (selection A)

8 0

3 years ago