Answer:
68% of jazz CDs play between 45 and 59 minutes.
Step-by-step explanation:
<u>The correct question is:</u> The playing time X of jazz CDs has the normal distribution with mean 52 and standard deviation 7; N(52, 7).
According to the 68-95-99.7 rule, what percentage of jazz CDs play between 45 and 59 minutes?
Let X = <u>playing time of jazz CDs</u>
SO, X ~ Normal(
)
The z-score probability distribution for the normal distribution is given by;
Z = 
~ N(0,1)
Now, according to the 68-95-99.7 rule, it is stated that;
- 68% of the data values lie within one standard deviation points from the mean.
- 95% of the data values lie within two standard deviation points from the mean.
- 99.7% of the data values lie within three standard deviation points from the mean.
Here, we have to find the percentage of jazz CDs play between 45 and 59 minutes;
For 45 minutes, z-score is = 
= -1
For 59 minutes, z-score is = 
= 1
This means that our data values lie within 1 standard deviation points, so it is stated that 68% of jazz CDs play between 45 and 59 minutes.
Answer:
The approximated length of EF is 2.2 units ⇒ A
Step-by-step explanation:
<em>The tangent ratio in the right triangle is the ratio between the opposite side to the adjacent side of one of the acute angle in the triangle</em>
In the given figure
∵ The triangle DFE has a right angle F
∵ The opposite side to angle D is EF
∵ The adjacent side to angle D is DF
→ By using the tangent ratio above
∴ tan(∠D) = 
∵ DF = 6 units
∵ m∠D = 20°
→ Substitute then in the ratio above
∴ tan(20°) = 
→ Multiply both sides by 6
∴ 6 tan(20°) = EF
∴ 2.183821406 = EF
→ Approximate it to the nearest tenth
∴ 2.2 = EF
∴ The approximated length of EF is 2.2 units
Answer: 2.9025
Step-by-step explanation:
0.75 x 387/100
= 2.9025
Answer:
y is going back by 3's x is going back one
Step-by-step explanation:
Answer:
The cost store owner pay for the pair of jeans is <u>$42</u>.
Step-by-step explanation:
Given:
A store owner uses a selling price of 125% of the cost of an item.
If a pair of jeans has a sales price of $52.50.
Now, to find the cost price of the store owner pay for the pair of jeans.
Let the cost price of jeans be 
Sell price of jeans = 
Now, to get the cost price of store owner pay for the pair of jeans:
<em>As given the</em><em> </em><em>store owner uses a selling price of 125% of the cost of an item.</em>
According to question:
<em>Dividing both sides by 1.25 we get:</em>
<em>The cost price of jeans = $42.</em>
Therefore, the cost store owner pay for the pair of jeans is $42.
