Prime numbers are numbers that have only one factor pair; 1 and themselves.
Let's start from 21.
21 = 1 x 21, 3 x 7.
This has two factor pairs, this is not prime.
Let's try 22.
22 = 1 x 22, 2 x 11.
This also has two factor pairs, this is not prime.
Let's try 23.
1 x 23.
This is a prime number, as it only has one factor pair; 1 and itself.
23 is your prime number.
I hope this helps!
Yes the probability of an outcome that lies within 68% is a good indicator that lies in which standard deviation.
Remember that

Thus, we can solve for x.
x + 22 = 90 - (2x - 7)
x + 22 = 97 - 2x
3x + 22 = 97
3x = 75
x = 25
Answer:
x = 7.99 cm
Step-by-step explanation:
By applying cosine rule in the given triangle,
AC² = AB² + BC² - 2(AB)(AC)cosC
Substitute the measures of the sides and the angle in this formula,
x² = 6² + 10² - 2(6)(10)cos(53°)
x² = 36 + 100 - 72.217
x² = 63.782
x = √(63.782)
x = 7.99 cm
The physical position of something.