The answer is 7 . you need to add up all the numbers & divide it by the numbers you have
Hey there!
The mean of the numbers is the <u>average</u>. To find the mean we will simply add all the numbers together, and divide them by the amount of numbers there are. Easy, peesy, lemon squeezy. Lets get started.
7 + 10 + 22 + 10 + 12 + 10 + 12 = 83
Now that we have added those altogether, we can divide them by the amount of numbers there are. The amount of numbers there are comes to a total of 7. Therefore...
83 divided by 7 = 11.857
Answer Choice B. 11.9 is your correct answer.
The answer is Difference of Cubes.
Difference of cubes is a³ - b³.
27 can be written as 3³ (= 3 × 3 × 3 = 27). So, a = 3.
8 can be written as 2³ (= 2 × 2 × 2 = 8). So, b = 2.
Difference of cubes can be expressed as:
a³ - b³ = (a - b)(a² + ab + b²)
⇒ 3³ - 2³ = (3 - 2)(3² + 3×2 + 2²) = 1 × (9 + 6 + 4) = 1 × 19 = 19
⇒ 27 - 8 = 19
Cobalt has an atomic number (Z) of 27, which means the nuclei of all its isotopes have 27 protons. Cobalt 60 has an atomic mass of 60, so it has 60-27 = 33 neutrons.
The mass of 27 isolated protons plus the mass of 33 isolated neutrons would be:
27*(1.007825 u) + 33*(1.008665 u) = 60.497220 u
The actual mass of the nucleus of 60-Co is 59.933820 u.
Mass defect: 60.497220 u - 59.933820 u = 0.563400 u
The mass defect is equal to the binding energy of a nucleus.
using the fact that 1 u = 931.5 MeV/c^2
(0.563400 u)*(931.5 MeV/u) = 524.807 MeV
