Hey there!
In order to calculate the mean you have to add up all up your given numbers (its the average number in total) then divide it by the total numbers you have
Example ⬇
Given: 3, 10, 45
Setting them up (Add) 3 + 10 + 45
Total numbers (Divide) : 3
➡ 3 + 10 + 45 = 58
➡ 58 / 3 = 19.3(repeated of 3)
Good luck on your assignment and enjoy your day!
~LoveYourselfFirst:)