Tuesday

July 22, 2014

July 22, 2014

Posted by **J** on Tuesday, March 6, 2007 at 5:15pm.

#1) A sample of 4 different calculators is randomly selected from a group containing 20 that are defective and 31 that have no defects. What is the probability that at least one of the calculators is defective?

(A) 0.863 (B) 0.874 (C) 0.200 (D) 0.126

My work:

(31/51)(30/50)(29/49)(28/48) = .1259

1 - .1259 = .8741

#2)A sample of 4 different calculators is randomly selected from a group containing 49 that are defective and 26 that have no defects. What is the probability that all four of the calculators selected are defective?

(A) 0.1822 (B) 0.0793 (C) 14.1724 (D) 0.1743

My work:

(49/75)(48/74)(47/73)(46/72) = .1743

#1. The probability that NONE are defective is 31/51 *30/50 * 29/49 * 28/48 = 0.1259

Probability of at least 1 = 1 - .1259 = .8741 . Correct

#2 Also correct

**Related Questions**

Math - I can not seem to figure out this question. Can someone please help? Two ...

math help please - I am having a hard time understanding recprocial with ...

math - I am not understanding this question. Can someone help me please? Decide...

physics - Two wires run from the top of a pole 2.6 tall that supports a ...

Physics - Two wires run from the top of a pole 2.6m tall that supports a ...

Psychology - I am having trouble understanding the following question: What ...

Statistics - a) What is sampling with replacement? (b) What is sampling without ...

probability - hydraulic landing assemblies coming from an aircraft rework ...

math - A box contains 12 lightbulbs. Find the number of ordered N samples of ...

Basic Math - I'm really stuck in this question can someone please help me out in...