A suitable probability calculator can tell you the probability is about 6.7%.
_____
The standard deviation of the distribution of sample means is the population standard deviation (6) divided by the square root of the sample size (√144=12). Thus, your threshold is about (19.25-20)/(6/12) = -1.5 standard deviations from the mean.
Given
Area of the regular pentagon is 6.9 cm².
Find out the perimeter of a regular pentagon
To proof
Formula
Area of regular pentagon is
As given in the question
area of regular pentagon = 6.9 cm²
now equating the area value with the area formula.
Now put
√5 = 2.24 ( approx)
put in the above equation
thus
a² = 4.01
a = √ 4.01
a = 2.0 cm ( approx)
As perimeter represented the sum of all sides.
i.e regular pentagon have five sides of equal length.
Thus
perimeter of the regular pentagon = 5 × side length
= 5 ×2.00
therefore the perimeter of the regular pentagon = 10cm
option c is correct
Hence proved
Answer:
± 3
Step-by-step explanation:
let n be the number then the number squared is n² , so
6n² = 54 ( divide both sides by 6 )
n² = 9 ( take the square root of both sides )
n = ± = ± 3
That is the number is 3 or - 3