Solve the Problem $\mathrm { f } ( \mathrm { x } )$

Multiple Choice

Solve the problem.
-In the following formula, $\mathrm { f } ( \mathrm { x } )$ is the minimum number of hours of studying required to attain a test score of $x : f ( x ) = \frac { 0.47 x } { 100.5 - x }$ . How many hours of study are needed to score 83 ?

A) $22.30 \mathrm { hr }$
B) $2.23 \mathrm { hr }$
C) $100.93 \mathrm { hr }$
D) $4.51 \mathrm { hr }$