Sajjad1994
If J and K are points in a plane and J lies inside the circle C with center O and radius 4, does K lie inside circle C?
(1) The length of line segment JK is 1
(2) The length of line segment OJ is 2.5
Solution:
Statement One Alone:
The length of line segment JK is 1.
We can’t determine whether K lies inside circle C or not based on the information given. For example, if J is very close to O, then K is inside the circle. However, if J is very close to the circumference of circle O, then K could be outside the circle. Statement one alone is not sufficient.
Statement Two Alone:
The length of line segment OJ is 2.5.
Since this doesn’t tell us anything about K, statement two alone is not sufficient.
Statements One and Two Together:
With the information from both statements, we see that line segment OK is no longer than JK + OJ = 1 + 2.5 = 3.5 (note: OK = 3.5 if points O, J and K are collinear; otherwise, OK < 3.5). Since the radius of circle C is 4, this means K must lie inside the circle. Both statements together are sufficient.
Answer: C