There are three points P, Q and R on a straight line such that PQ : QR = 3 : 5. If n is the number of possible values of PQ : PR, then what is n equal to ?
2
Given:
PQ : QR = 3 : 5
Calculation:
CASE - 1
Assuming PQ = 3x, QR = 5x and PR = PQ + QR, we get
PQ : PR = 3x : (3x + 5x)
⇒ PQ : PR = 3 : 8
CASE - 2
Assuming PQ = 3x, QR = 5x and PR = QR - PQ, we get
PQ : PR = 3x : (5x - 3x)
⇒ PQ : PR = 3 : 2
So, we have n = 2 possible values.
Hence, option 2 is correct.
The order of points is not fixed. So, we have to check for all other possible cases.
Mistake Points
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