Ryan is correct, the mean is about 8.1.
To find the mean, you have to add up all the values, then divide by the total amount.
For Sample A:
60 x 6 + 90 x 7 + 145 x 8 + 150 x 9 + 55 x 10 = 4050
If you add up all the adults, you have 500.
Dividing 4050 by 500 = 8.1
Sample B will produce a very similar result.
Factors can be multiplied together to get the original number.
For example here are the factors of 66.
1 and 66. 2 and 33. 3 and 22. 6 and 11.
1 multiplied by 66 results in the original number 66.
2 multiplied by 33 results in the original number 66.
3 multiplied by 22 results in the original number 66.
<span>6 multiplied by 11 results in the original number 66.</span>
I assume you mean the equation
Since i = √(-1), we have i⁴ = 1 and so i⁵ = i. Then 2x + 3 must be some multiple of 5.
Now just check for which of the given choices that this holds:
x = 16 ⇒ 2x + 3 = 35 (yes)
x = 11 ⇒ 2x + 3 = 25 (yes)
x = 10 ⇒ 2x + 3 = 23 (no)
x = 14 ⇒ 2x + 3 = 31 (no)
