Answer:
9 fits perfectly...not sure why there's a range....
Answer:
A
Step-by-step explanation:
Hopefully this helps
Answer:
The approximate percentage of women with platelet counts within 3 standard deviations of the mean is 99.7%.
Step-by-step explanation:
We are given that the blood platelet counts of a group of women have a bell-shaped distribution with a mean of 247.3 and a standard deviation of 60.7.
Let X = <em>t</em><u><em>he blood platelet counts of a group of women</em></u>
The z-score probability distribution for the normal distribution is given by;
Z =
~ N(0,1)
where,
= population mean = 247.3
= standard deviation = 60.7
Now, according to the empirical rule;
- 68% of the data values lie within one standard deviation of the mean.
- 95% of the data values lie within two standard deviations of the mean.
- 99.7% of the data values lie within three standard deviations of the mean.
Since it is stated that we have to calculate the approximate percentage of women with platelet counts within 3 standard deviations of the mean, or between 65.2 and 429.4, i.e;
z-score for 65.2 = 
=
= -3
z-score for 429.4 = 
=
= 3
So, it means that the approximate percentage of women with platelet counts within 3 standard deviations of the mean is 99.7%.
Answer:
see explanation
Step-by-step explanation:
Using the tangent ratio in the right triangle
tan A =
=
=
, then
∠ A =
(
) ≈ 41° ( to the nearest degree )
The sum of the angles in the triangle = 180° , then
∠ B + 41° + 90° = 180°
∠ B + 131° = 180° ( subtract 131° from both sides )
∠ B = 49°
Using Pythagoras' identity in the right triangle
AB² = BC² + AC² = 7² + 8² = 49 + 64 = 113 ( take square root of both sides )
AB =
≈ 10.6 ( to the nearest tenth )