SOLUTION: The pressure of the gas is directly proportional to the temperature and inversely proportional to its volume. A. Write the variation equation. B. What will happen to the press

For all proportion problems, start with this:

Varying           "directly" or product of "jointlys" or 1 if none 
quantity  = k × ----------------------------------------------------------
                inversely variable or product of "inverselys" or 1 if none

In this problem the varying quantity is P for pressure. The "directly" is T for
temperature.  We have one "inversely" variable, T for Volume.  We have no
"jointly" variable. So we have P on the left, T on the top of the fraction and
V on the bottom:



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Let's substitute 2V for V in , and  for P and simplify:



We simplify the complicated term 

Since  is 4 times , the answer to B is:

"The pressure will quadruple."

Edwin