Answer:
B. 61%
Step-by-step explanation:
When we have the standard deviation of a sample, we use the t-distribution.
The width of an interval is related to the margin of error, which is given by the following equation:
M = T*s
In which T is related to the confidence level(and the sample size) and s is the standard deviation of the sample. Higher confidence levels have higher values of T.
A higher margin of error means that the interval is wider. To have a higher margin of error, we desire a higher value of T, which is achieved with a higher confidence level.
So the correct answer is:
B. 61%
Answer:
31.25 percent increase
Step-by-step explanation:
To find the percent increase, we take
percent increase = (new - original)/new * 100 percent
= (420-320)/320 * 100 percent
100/320 * 100 percent
.3125 * 100 percent
31.25 percent increase
Answer:
Chocolate is now a sweet treat that is very popular in the united states.
Step-by-step explanation:
Answer:
b. 2.28%.
Step-by-step explanation:
Mean temperatue (μ) = 1000°F
Standard Deviation (σ) = 50
°F
For any temperature value, X, the z-score is given by:
For X= 900°F

A z-score of -2.0 corresponds to the 2.28-th percentile of a normal distribution. Therefore, the probability that X<900 is:
