Jim can wash 3 cars in one hour, while his brother
David can wash 4 cars in x hours. Together, the
brothers can wash 12 cars in x hours. The equation
above represents the situation described. Which of
the following describes what the expression -
represents in this equation?
12
A) The time, in hours, that it takes both men to wash
12 cars
B)
The amount by which Jim's rate of work exceeds
David's rate of work
C) The combined rate of work of both men
D)
The amount by which David's rate of work
exceeds Jim's rate of work