At the end of year X, automobile installment credit accounted for 43% of all outstanding consumer installment credit. At that time automobile finance companies extended $50 billion of credit, or 1/4 of the automobile installment credit. How many billion dollars of consumer installment credit was outstanding at that time?	Choose one:
A) 450
B) 465.12
C) 475
D) 500.15
E) 200

Rationale: system of equations a = ( 43 / 100 ) c ( 1 / 4 ) a = 50 - - > a = 200 substitution 200 = ( 43 / 100 ) c c = ( 100 / 43 ) 200 calculate 200 / 43 * 100 - the the correct answer is 465.12 . the correct answer is b .
Answer: B