Find the total allotted time:
Let n be the total allotted time
2.5th decile = 35
2.5 decile ⇒ 2.5/10 ⇒ 0.25
0.25n = 35
0.25n/0.25 = 35/0.25
n = 140 minutes, the total time allotted to finish the test.
ANSWER: Out of 140 minutes allotted time, the students finished the test in 35 minutes. They still have spare time of 105 minutes, meaning the students were quick in answering the test.