At the end of year X, automobile installment credit accounted for 36% of all outstanding consumer installment credit. At that time automobile finance companies extended $57 billion of credit, or 1/3 of the automobile installment credit. How many billion dollars of consumer installment credit was outstanding at that time?

A. 62

B. 171

C. 475

D. 513

E. 684

475 billion dollars

Step-by-step explanation:

Let P be the customer credit

At the end of year X, 36% of P is gotten from automobile installment credit

57 billion credit is 1/3 of the automobile installment credit. This means that the total automobile installment credit 57*3 = 171 billion dollars

36% * P = 171

36/100 * P = 171

36P = 171 * 100

P = 17100/36

P = 475 billion dollars