The lengths of text messages are normally distributed with an unknown population mean. A random sample of text messages is taken
2 answers:
Answer:
95% of the text messages have length between 23 units and 47 units.
Step-by-step explanation:
We are given the following in the question:
The lengths of text messages are normally distributed.
95% confidence interval:
(23,47)
Thus, we could interpret the confidence interval as:
About 95% of the text messages have length between 23 units and 47 units.
By Empirical rule for a normally distributed data, about 95% of data lies within 2 standard deviations of mean , thus we can write:
Thus, the mean length of text messages is 23 units and standard deviation is 6 units.
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Remember that an extraneous solution of an equation is a solution that emerges from the algebraic process of solving the equation but is not a valid solution of the equation.
First, we are going to solve our equation algebraically:
Step 1 simplify the equation:
Step 2 subtract 5 from both sides of the equation:
Step 3 square both sides of the equation:
Next, we are going to replace our solution in our original equation and check if it is a valid solution:
Since 9 is not equal to 1, is not valid solution of the equation; therefor it is an extraneous solution.
We can conclude that the correct answer is: x = 16, solution is extraneous
Answer:
OPtion I is right
Step-by-step explanation:
Once we know sin of an angle, and it lies in II quadrant, we know that
cos, sec, tan and cot would be negative but csc will be positive.
So use the fact that
Thus cos is obtained using negative square root.
Now tan = sin/cos, and sec = 1/cos:
cot =1/tan and csc =1/sin
Thus all value can be obtained easily
So option I