Assume that random quesses are made for seven multiple choice questions on an SAT test, so that there are N = 7 trials, each with probability of success (correct) given by p = 0.55. Find the indicated probability for the number of correct answers. Find the probability that the nmber x of correct answers is fewer than 4.P(X<4) = A survey showed that 72% of adults need correction (eyeglasses, contacts, surgery etc) for their eyesight. If 21 adults are randomly selected , find the probability that at least 20 of them need correction for their eyesight. Is 20 significantly high number of adults requiring eyesight correction?

Since you have asked multiple questions, we will solve the first question for you. If you want any specific question to be solved then please specify the question number or post only that question. The binomial probability distribution is, PX=x=nxpx1-pn-x In the formula, n denotes the number of trails, p denotes probability of success, and x denotes the number of success. The random variable X is defined as the number of correct answers which follows binomial distribution with sample size 7, and probability of success 0.55.The probability that the number of correct answers is fewer than 4 is, PX<4=PX=0+PX=1+PX=2+PX=3=700.5501-0.557-0+710.5511-0.557-1+720.5521-0.557-2+730.5531-0.557-3=0.0037+0.0320+0.1172+0.2388=0.3917 Thus, the probability that the number of correct answers is fewer than 4 is 0.3917.

Math

Probability

Assume that random quesses are made for seven multiple choice questions on an SAT test, so that there are N = 7 trials, each with probability of success (correct) given by p = 0.55. Find the indicated probability for the number of correct answers. Find the probability that the nmber x of correct answers is fewer than 4. P(X<4) =

Assume that random quesses are made for seven multiple choice questions on an SAT test, so that there are N = 7 trials, each with probability of success (correct) given by p = 0.55. Find the indicated probability for the number of correct answers. Find the probability that the nmber x of correct answers is fewer than 4. P(X<4) =

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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