Answer:
The standard deviation of that data set is 3.8
Step-by-step explanation:
The Empirical Rule states that, for a normally distributed random variable:
68% of the measures are within 1 standard deviation of the mean.
95% of the measures are within 2 standard deviation of the mean.
99.7% of the measures are within 3 standard deviations of the mean.
In this problem, we have that:
Mean = 55
95% of the data fall between 47.4 and 62.6. This means that 47.4 is 2 standard deviations below the mean and 62.6 is two standard deviations above the mean.
Using one of these points.
55 + 2sd = 62.6
2sd = 7.6
sd = 7.6/2
sd = 3.8
The standard deviation of that data set is 3.8
Answer:
8
Step-by-step explanation:
Given the equation 1/4 (16 + 12x) = 28, to solve this first we open the bracket using the distributive property. According to this property, given A, B and C then:
A(B+C ) = AB+AC
Step 1:
1/4 (16 + 12x) = 28
= 1/4(16)+1/4(12x) = 28
= 4+3x = 28
Step 2:
We move 4 to the other side to have:
3x = 28-4
3x = 24
Step 3:
Divide both sides by 3 to have,:
3x/3 = 24/3
x = 8
The answer is 8
<span>Let x be the number of songs downloaded.
Each song is $1.29; the total cost would be found by multiplying the cost by the number of songs, or 1.29x.
This cannot be more than 20, so we set this less than or equal to 20:
1.29x ≤ 20.
<u>To solve this, we divide both sides by 1.29: </u>
</span>

<span> ≤ </span>

<span>;
x ≤15.5.
We <u>cannot download half of a song</u>, so we round this down to 15 (although the number rounds up mathematically, he would not have enough money to download 16 songs). This means he can download at most 15 songs.</span>
The correct answer is b=3+1/2 divided by 5+3 after that +10-3*5*3 . add the answers up and thats the solution