A survey showed that 82% of adults need correction (eyeglasses, contacts, surgery, etc.) for their eyesight. If 12 adults are randomly selected, find the probability that at least 11 of them need correction for their eyesight. Is 11 a significantly high number of adults requiring eyesight correction?
Accepted Solution
A:
Probability of an adult who needs correction = 82% or 0.82So, probability of an adult who does not needs correction = 1 - 0.82 = 0.18If 12 adults are randomly selected, the probability that at least 11 of them need correction for their eyesight is: 12C11[tex](0.82)^{11}(0.18)^{12-11}[/tex] + 12C12[tex](0.82)^{12}(0.18)^{12-12}[/tex]= 12*0.11*0.18 + 1*0.09*1= 0.238+0.09 = 0.328 or 0.33And, yes, 11 is significantly a high number of adults requiring eyesight correction.