Three points X, Y, Z are on a straight line such that XY= 10 and XZ = 3. What is the product of all possible values of YZ?

Answer: 91
One by one keep X,Y,Z in middle and see what are the possible options.
Only X---3--Z--7--Y and Z--3--X--10--Y are possible.
So answer = 7*13 = 91

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