A survey showed that 81% of adults need correction (eyeglasses, contacts, surgery, etc.) for their eyesight. If 11 adults are randomly selected, find the probability that no more than 1 of them need correction for their eyesight. Is 1 a significantly low number of adults requiring eyesight correction?

The probability that no more than 1 of the 11 adults require eyesight correction is

5.579 * or  0.00005579 %

Step-by-step explanation:

In this question, you select 11 random adults, so the order is not important and we should use combination instead of permutation. There are two different probability here

A= chance that the adults need correction= 0.81

B= chance that the adult doesn't need correction = 0.19

The case that can fulfill the condition of no more than 1 of 11 adults need correction is:

1. 0 adult need correction = 0C11 *

2. 1 adult need correction = 1C11 * *

Then the probability will be:

0C11 * +1C11 * * =

 *     +     * *0.81 =

5.579 * = 0.00005579 %

The threshold for a significant value that widely used is 5% and the chance is lower than 5%, so no more than 1 adult need correction is a significantly low number of adults requiring eyesight correction?

ad = ae + ed = y + 7

similar triangles therefor

ac/ab = ad/ae

6/4 = (y + 7) / y

cross multiply

6y = 4(y + 7)

6y = 4y + 28

2y = 28

y = 14

step-by-step explanation:

45

step-by-step explanation: