A letter lock consists of three rings each marked with six different letters. The number of distinct unsuccessful attempts to open the lock is at the most  Choose the correct choice from the following.
A) 272	B) 277	C) 215	D) 187	E) 165
Since each ring consists of six different letters, the total number of attempts possible with the three rings is = 6 * 6 * 6= 
<gadget id="calculator">6 * 6 * 6</gadget>
<output>216</output>
216. Of these attempts, one of them is a successful attempt.   Maximum number of unsuccessful attempts= 216 - 1= 
<gadget id="calculator">216 - 1</gadget>
<output>215</output>
215   Answer:215
<result>C</result>
A letter lock consists of three rings each marked with six different letters. The number of distinct unsuccessful attempts to open the lock is at the most