Time (in minutes) Number of Problems in Set

30                            36

40                            48

50                            60

60                             72

The time it took Tanya to complete different sets of math problems varied directly with the number of problems in the set. Tanya’s data is shown in the table. If x = time, and y = the number of problems in the set, which equation models Tanya’s direct variation?

A) y = 12x  

B) y = 1.2x  

C) y = x + 12  

D) y = x + 1.2