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A consignment of 15 record players contains 4
\( \mathrm{P} \) defectives. The record players are selected at

W random, one by one, and examined. The ones examined are not put back. The probability that \( 9^{\text {th }} \) one examined is the last defective, is
(1) \( \frac{{ }^{4} C_{3} \times{ }^{11} C_{5}}{{ }^{15} C_{8}} \)
(2) \( \frac{{ }^{4} C_{3} \times{ }^{11} C_{5}}{{ }^{15} C_{8}} \times \frac{1}{7} \)
(3) \( \frac{{ }^{11} C_{5}}{{ }^{15} C_{8}} \times \frac{1}{7} \)
(4) \( \frac{{ }^{4} C_{3}}{{ }^{11} C_{5}} \times \frac{1}{7} \)
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