Answer:
The probability that no more than more than 11 of them need correction for their eyesight is 0.00512
No, 11 is not a significantly low low number of adults requiring eyesight correction .
Step-by-step explanation:
A survey showed that 77% of adults need correction for their eyesight.
If 22 adults are randomly selected, find the probability that no more than more than 11 of them need correction for their eyesight.
n =22
p = 0.77
q = 1-p = 1- 0.77=0.23
We are supposed to find [tex]P(x\leq 11)[/tex]
[tex]P(x\leq 11)=P(x=1)+P(x=2)+P(x=3)+.....+P(x=11)[/tex]
Formula : [tex]P(x=r)=^nC_r p^r q^{n-r}[/tex]
[tex]P(x\leq 11)=^{22}C_1 (0.77)^1 (0.23)^{22-1}+^{22}C_2 (0.77)^2 (0.23)^{22-2}+^{22}C_3 (0.77)^1 (0.23)^{22-3}+.....+^{22}C_{11} (0.77)^1 (0.23)^{22-11}[/tex]
Using calculator
[tex]P(x\leq 11)=0.00512[/tex]
So, The probability that no more than more than 11 of them need correction for their eyesight is 0.00512
No, 11 is not a significantly low low number of adults requiring eyesight correction .