The probability that an individual has 20-20 vision is 0.19 0.19. in a class of 70 70 students, what is the mean and standard deviation of the number with 20-20 vision in the class? round to the nearest thousandth.

Formula to find mean and standard deviation is,

Means = np and standard deviation =.

Where n= sample size, p = probability.

According to the given problem, the probability that an individual has 20 vision is 0.19 in a class of 70 students. So,

p = 0.19 and n = 70.

Hence, the first step is to plug in these values in the above formula to get mean and standard deviation. Therefore,

Mean = np

= 70* 0.19

= 13.3

= 13.300 (Rounded to nearest thousandth.

Standard deviation =

=

=

=√10.773

=3.282224855

= 3.282 (Rounded to nearest thousandth).

simplifying

5(x + -6) = 2(x + 3)

reorder the terms:

5(-6 + x) = 2(x + 3)

(-6 * 5 + x * 5) = 2(x + 3)

(-30 + 5x) = 2(x + 3)

reorder the terms:

-30 + 5x = 2(3 + x)

-30 + 5x = (3 * 2 + x * 2)

-30 + 5x = (6 + 2x)

solving

-30 + 5x = 6 + 2x

solving for variable 'x'.

move all terms containing x to the left, all other terms to the right.

add '-2x' to each side of the equation.

-30 + 5x + -2x = 6 + 2x + -2x

combine like terms: 5x + -2x = 3x

-30 + 3x = 6 + 2x + -2x

combine like terms: 2x + -2x = 0

-30 + 3x = 6 + 0

-30 + 3x = 6

add '30' to each side of the equation.

-30 + 30 + 3x = 6 + 30

combine like terms: -30 + 30 = 0

0 + 3x = 6 + 30

3x = 6 + 30

combine like terms: 6 + 30 = 36

3x = 36

divide each side by '3'.

x = 12

simplifying

x = 12

this should .

i think the answer is b