Evildoer's plot
10 superheroes are caught by an evildoer. The 10th superhero is guaranteed to live, while the probability of the 9th superhero is 90%, the 8th superhero's probability being 80%, the 7th sure hero's probability being 70% and so on. What is the probability they all survive? Round to the nearest thousandth. Put your answer after you convert it to percent. (i.e you got 0.006985 without multiplying by 100 you would put in 0.699)
The answer is 0.036.
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I think the question is somewhat ambiguous. I would argue the correct answer to the question as written should be .363.
The issue is the probability of the tenth supper hero living. It could be argued that continuing with the pattern set by the numbered superheroes 2 through 9 the probability of the tenth superhero living would be 1 (guaranteed to live) not 10% as the answer implies. Following the pattern given it would be the first (#1) superhero that would have a 10% probability to living but we where told he was guaranteed to live which is not consistent with the pattern for the others.
If superhero #10 is consistent with the others he would also be guaranteed to live. So the sequence would be 1 x .2 x .3 x .4 x .5 x .6 x .7 x .8 x .9 X 1 = .363%. :)