In the triangle below, P is the centroid, PF = 6 and AD = 15. What is the measure of AP ?
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Explanation:
The centroid cuts the medians in such a way that AP is twice as long as PD
Let PD be equal to x. This means AP is 2x
The two pieces add to AP+PD = 2x+x = 3x = AD
Since AD = 15, we can then say,
AD = 15
3x = 15
x = 15/3
x = 5
Therefore,
PD = x = 5
AP = 2x = 2*5 = 10
This leads to answer choice C.