/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 59 Slippery Elum is a baseball pitc... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

Slippery Elum is a baseball pitcher who uses three pitches, \(60 \%\) fastballs, \(25 \%\) curveballs, and the rest spitballs. Slippery is pretty accurate with his fastball (about \(70 \%\) are strikes), less accurate with his curveball (50\% strikes), and very wild with his spitball (only \(30 \%\) strikes). Slippery ends one game with a strike on the last pitch he throws. What is the probability that pitch was a curveball?

Short Answer

Expert verified
The probability that the last pitch was a curveball given that it resulted in a strike is approximately 21.19\%.

Step by step solution

01

Determine the Probability for Each Type of Pitch

We know that Slippery Elum uses three pitches, with the following probabilities:\nFastballs: \(0.60 or 60\% \)\nCurveballs: \(0.25 or 25\% \)\nSpitballs: \(0.15 or 15\% \) - This is because we know that the rest of the pitches are all spitballs. (100% - 60% - 25% = 15%)
02

Determine the Probability of a Strike for Each Type of Pitch

We also know the likelihood of a strike for each type of pitch, which is represented as such:\nFastball strike: \(0.70 or 70\% \)\nCurveball strike: \(0.50 or 50\% \)\nSpitball strike: \(0.30 or 30\% \)
03

Use Bayes' Theorem

Now we can use Bayes’ theorem to calculate the exact probability that the last pitch was a curveball given that it was a strike. Bayes' theorem can be used as follows for this problem:\n\(P(Curveball|Strike) = (P(Strike|Curveball) * P(Curveball)) / P(Strike)\)\nThe probability of a strike, P(Strike), can be calculated as follows:\nP(Strike) = P(Strike and Fastball) + P(Strike and Curveball) + P(Strike and Spitball) = (P(Strike|Fastball) * P(Fastball)) + (P(Strike|Curveball) * P(Curveball)) + (P(Strike|Spitball) * P(Spitball))\nUsing the given values, the probabilities become: \nP(Strike) = (0.70 * 0.60) + (0.50 * 0.25) + (0.30 * 0.15) = 0.42 + 0.125 + 0.045 = 0.59. \nNow, we can substitute all the values into Bayes' theorem to find the required probability:\nP(Curveball|Strike) = (0.50 * 0.25) / 0.59 = 0.2119 or 21.19\%.

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