There are three points P, Q and R on a straight line such that PQ : QR = 3 : 5. If n is the number of…
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?
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Solution
With PQ : QR = 3 : 5, the points can be ordered so that Q lies between P and R (PR = PQ + QR = 8, giving PQ : PR = 3 : 8) or so that P lies between R and Q (PR = QR - PQ = 2, giving PQ : PR = 3 : 2). These are the only two distinct values, so n = 2.