Ms. Rodriguez is comparing data about the number of leaf samples tested by three scientists in each of two laboratories. The tables show the number of leaf samples tested and the time spent testing.
Laboratory A Laboratory B
Scientist Number of Leaf
Samples Tested Time Spent
(minutes) Scientist Number of Leaf
Samples Tested Time Spent
(minutes)
Steve 90 30 Mary 140 35
Jesmy 180 45 Brian 160 40
Buck 210 60 Kate 220 55
Which laboratory shows a proportional relationship between the number of leaf samples tested and the time spent testing?
A.
only laboratory B
B.
only laboratory A
C.
neither laboratory A nor laboratory B
D.
both laboratory A and laboratory B