Are the 2 triangles congruent? If so, what postulate did you use?

The pulse rates of 174 randomly selected adult males vary from a low of 39 bpm to a high of 111 bpm. Find the minimum sample siz

Daniel [21]

Answer:

a. The sample size is approximately 97 adults

Step-by-step explanation:

The given parameters are;

The number of adults surveyed, n = 174

The lowest value of the pulse rate = 39 bpm

The highest value of the pulse rate = 111 bpm

The level of confidence used for determining the sample size = 90%

The given sample mean = 3 pm of the population mean

a. The range rule of thumb states that the standard deviation is approximately one quarter (1/4) of the range

The range = 111 bpm - 39 bpm = 72 bpm

Therefore, the standard deviation, σ = 72 bpm/4 = 18 bpm

The sample size, 'N', is given as follows;

$N = \dfrac{z^2 \cdot p \cdot q}{e^2}$

Where;

N = The sample size

z = The confidence level, 90% (z-score at 90% = 1.645)

p·q = σ² = 18² = 324

e² = 3² = 9

$N = \dfrac{1.645^2 \times 324}{3^2} = 97.4169$

Therefore the appropriate sample size, N ≈ 97 adults.

8 0

3 years ago

Lf oil costs $95 per barrel and $1 =R8. How much does a barrel cost in rands?.

Elan Coil [88]

Answer:

R760

Step-by-step explanation:

If $1 is equivalent to R8 and the total oil costs $95 you must multiply 8x95. This leaves you with an answer of R760

7 0

3 years ago

A craft store has 5 yards and 2 inches of ribbon. The cost of the ribbon is calculated per inch. How many inches of

suter [353]

Answer:

182

Step-by-step explanation:

5 yards = 5*3 = 15 feet

15 feet = 15 * 12 = 180 inches.

There are 2 more inches in the ribbon. 180 + 2 = 182 inches.

3 0

3 years ago

At a Psychology final exam, the scores are normally distributed with a mean 73 points and a standard deviation of 10.6 points. T

USPshnik [31]

Answer:

The score that separates the lower 5% of the class from the rest of the class is 55.6.

Step-by-step explanation:

Problems of normally distributed samples can be solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

In this question:

$\mu = 73, \sigma = 10.6$