The z-score associated with 14.3 is 0.84. 0.2995 of the population is between 12.2 and 14.3. 0.1894 of the population is less than 10.0.
The formula for a z-score is
z=(X-μ)/σ
With our data, we have:
z=(14.3-12.2)/2.5=0.84
The z-score associated with the mean is 0.5. To find the proportion of the population between the mean and 14.3, subtract 0.7995 (the proportion of population below the z-score of 0.84, using http://www.z-table.com) and 0.5:
0.7995 - 0.5 = 0.2995.
The z-score for 10.0 is
(10.0-12.2)/2.5 = -0.88. The proportion of the population less than this is 0.1894.
I believe you convert from Kelvin to Degree Fahrenheit
Kelvin is 293 so
F=9/5 (293-273.15)+32
F=9x5 (19.85)+32
F=45-19.85+32
F=57.15
Since we know that 1/4 is equal to 25%, or 0.25 in decimal form, we are able to work with 0.75 in the expression.
We are told to use j as the original price of the jeans, so we can set up the expression:
to represent the cost of the jeans with the discount.
Then to simplify, we simply take out j as a common factor, and solve what's in the parentheses:
or 
Using this equation, we can solve for the b part of the question. If the pair of jeans originally costs $60, plug in 60 to where j is in the expression:
Therefore, the cost of the jeans after the discount is C) $45.
1/4n-8=1/4 would be first because it says less than so you switch it. then you put the 8 since it's in the same subtraction problem. Then the word "is" indicates the equal sign. and the n represents "a number" since it is unknown.
Answer: I'm not entirely sure, but maybe 1/x^2?
