Answer:
0.0359
Step-by-step explanation:
Data provided:
mean values of three independent times are 15, 30, and 20 minutes
the standard deviations are 2, 1, and 1.6 minutes
Now,
New Mean = 15 + 30 + 25 = 65
Variance = ( standard deviation )²
or
Variance = 2² + 1² + 1.6² = 7.56
therefore,
Standard deviation = √variance
or
Standard deviation = 2.75
Thus,
Z-value = 
or
Z-value = - 1.81
from the Z-table
the Probability of Z ≤ -1.81 = 0.0359
Rotation is a type of transformation refered to a in which the shape of the original object is preserved and the angle of rotation is constanf for all the parts of the body.
Thus, when <span>ΔDEF rotates 90° clockwise about point A to create ΔD 'E 'F.
</span><span>m∠EAE ' = m∠FAF '</span>
Consider this option:
C³₂₇=27!/(3!*24!)=25*13*9=2925 ways to select 3 students.
Answer:
<h2>√512 by √512 </h2>
Step-by-step explanation:
Length the length and breadth of the rectangle be x and y.
Area of the rectangle A = Length * breadth
Perimeter P = 2(Length + Breadth)
A = xy and P = 2(x+y)
If the area of the rectangle is 512m², then 512 = xy
x = 512/y
Substituting x = 512/y into the formula for calculating the perimeter;
P = 2(512/y + y)
P = 1024/y + 2y
To get the value of y, we will set dP/dy to zero and solve.
dP/dy = -1024y⁻² + 2
-1024y⁻² + 2 = 0
-1024y⁻² = -2
512y⁻² = 1
y⁻² = 1/512
1/y² = 1/512
y² = 512
y = √512 m
On testing for minimum, we must know that the perimeter is at the minimum when y = √512
From xy = 512
x(√512) = 512
x = 512/√512
On rationalizing, x = 512/√512 * √512 /√512
x = 512√512 /512
x = √512 m
Hence, the dimensions of a rectangle is √512 m by √512 m
