The set given by the project grade is {1, 2, 3, 4, 5}. If the random variable, X, is the project grade, the mean of the probability distribution is determined by:
Sum = 1 + 2 + 3 + 4 +5
= 15
Mean of the probability distribution is 15/n, where n = 5
= 15/ 5
= 3
If you're referring to the different sets of real numbers, it's the ones that you could try to do subtraction and not get an answer that still in that set.
For example, natural numbers (aka 1, 2, 3, 4, ...) are not, because 7 - 11 = -4 and -4 is not a natural number.
Also, whole numbers (aka 0, 1, 2, 3, 4, ...) has the same issue.
Basically any set of real numbers that doesn't include negative numbers will have this issue.
Draw out a horizontal line. Place 0 at the center. Then place evenly spaced tick marks on either side of 0. Label the right side of tick marks as 1, 2, 3, ... moving from 0 and going to the right
Label the left side of tick marks -1, -2, -3, ... starting at 0 and moving left
The location -3 on the number line is exactly 3 units away from 0. We start at 0 and move to -3 by moving 3 spots to the left; or we start at -3 and move 3 units to the right to get to 0.
Therefore, the absolute value of -3 is 3
Absolute value on a number line is the distance a number is from 0
The distance is never negative
Answer:
B
Step-by-step explanation:
Using the cosine ratio in the right triangle and the exact value
cos45° = 
, then
cos45° = 
= 
= ( cross- multiply )
c = 3
He has 30 gallons left
5/8 = 50/80
80-50=30
