Answer:

Step-by-step explanation:
Given

Required
Determine the value of T

Multiply both sides by 2


Divide through by 6




<span>At least 75% of the data will fall within 2 standard deviations of the mean.
This is tricky problem. Usually when you're dealing with standard deviation, you have a bell curve, or something close to a bell curve and for such a data distribution, there will be approximately 95% of the data within 2 standard deviations of the mean. But if you don't know that you have a bell curve, you have to fall back to Chebyshev’s Theorem, which states that at least 75% of the data points will fall within 2 standard deviations of the mean for any set of numbers.</span>
Let the price of 1 shirt be represented by = s
A pair of pants costs twice as much as a shirt, then the cost of pants is = 2s
The total cost of 1 pair of pants and 1 shirt is $18 , means : 
Solving this we get,


So, the price of 1 shirt is $6 and price of 1 pair of pants is = 2s = 2*6 = $12.