Answer: 54-7n
Step-by-step explanation:
When we talk about mathematical language, the <u>difference </u>between two numbers, quantities or terms is the <u>substraction operation.</u>
For example, the <u>difference</u> between a and b is:
a-b
On the other hand, if we read a numer c <u>times</u> a number n, this means both numbers are multiplied.
For example:
c <u>times</u> n is:
(c)(n)
So, according to the explained above, “the difference of fifty-four and seven times a number n” is:
54-7n
Answer:
t= 0.4933
t ≥ t ( 0.025 ,8 ) = 2.306
Since the calculated value of t= 0.4933 is less than t ( 0.025 ,8 ) = 2.306 therefore we accept the null hypothesis at 5 % significance level . On the basis of this we conclude that the book had no effect on their scores.
Step-by-step explanation:
We state our null and alternative hypotheses as
H0: ud= 0 Ha: ud≠0
The significance level is set at ∝= 0.05
The test statistic under H0 is
t= d`/ sd/√n
which has t distribution with n-1 degrees of freedom
The critical region is t ≥ t ( 0.025 ,8 ) = 2.306
Computations
Student Scores before Scores after Difference d²
reading book ( after minus before)
1 720 740 20 400
2 860 860 0 0
3 850 840 -10 100
4 880 920 40 1600
5 860 890 30 900
6 710 720 10 100
7 850 840 -10 100
8 1200 1240 40 1600
<u>9 950 970 20 40</u>
<u>∑ 6930 8020 140 4840</u>
d`= ∑d/n= 140/9= 15.566
sd²= 1/8( 4840- 140²/9) = 1/8 (4840 - 2177.778) = 2662.22/8= 332.775
sd= 18.2422
t= 3/ 18.2422/ √9
t= 0.4933
Since the calculated value of t= 0.4933 is less than t ( 0.025 ,8 ) = 2.306 therefore we accept the null hypothesis at 5 % significance level . On the basis of this we conclude that the book had no effect on their scores.
Answer:
The scale factor is 0.25
Step-by-step explanation:
we know that
The dilation is a non-rigid transformation that produce similar figures
If two figures are similar, then the ratio of its corresponding sides is proportional and this ratio is called the scale factor
In this problem
ABCD and A'B'C'D' are similar
therefore

Find the scale factor
Looking at the graph
we have

Let
z ---> the scale factor

substitute the values

2(x + 3) = x - 4
distribute
2x + 6 = x - 4
either subtract 6 from both sides or add 4. i will be subtracting 6.
2x = x - 10
subtract x from both sides
x = -10
Answer:
$30
Step-by-step explanation:
To find the original price, divide the new price by 0.8
24/0.8
= 30
So, the original price was $30