Carcass wrote:
The quantities S and T are positive and are related by the equation S = k/T, where k is a constant. If the value of S increases by 50 percent, then the value of T decreases by what percent?
A) 25%
B) 33 and \(\frac{1}{3}%\)
C) 50%
D) 66 and \(\frac{2}{3}\)%
E) 75%
Another approach it to first find some values that satisfy the condition that S = K/T
How about S = 2, K = 2 and T = 1 (since 2 = 2/1)
Now what happens to T if we increase S by 50%?
Well, if we increase 2 (the value of T) by 50%, we get S = 3
K is constant, so K = 2 (still)
What must T equal?
Take S = K/T and plug in the new value of S to get 3 = 2/T (and now solve for T)
To do so, multiply both sides by T to get: 3T = 2
Now divide both sides by 3 to get: T = 2/3
So, the value of T has DECREASED from 1 to 2/3
This represents a 33 1/3% decrease
Answer: B
Cheers,
Brent
_________________
Brent Hanneson - founder of Greenlight Test Prep