Variance of a continuous random variable X is defined as
Standard deviation is defined as
Hence standard deviation is the positive square root of variance.
Answer:
infinite solutions
Step-by-step explanation:
sub to PewDiePie if you haven't already
Step-by-step explanation:
2×length + 2×width = 45
length = 4×width
now, we are using the second equation (a variable identity) in the first equation
2×4×width + 2×width = 45
8×width + 2×width = 45
10×width = 45
width = 45/10 = 4.5 in
length = 4×width = 4×4.5 = 18 in
the area of the rectangle is
length × width = 18 × 4.5 = 81 in²
Well, if Tina can make 3 pies in one hour, she have to do 6 pies and she have already 2 so she can have as many pies as Bella, so the answer is 2 hours
