Answer:
0.8185 or 81.85%
Step-by-step explanation:
The mean length (μ) of an adult foot is 11 and the standard deviation (σ) is 1.5.
The z score is a measure in statistic used to determine the amount of standard deviation by which the raw score (x) is above or below the mean. If the raw score is above the mean, the z score is positive and if the raw score is below the mean the z sore is negative. It is given by:

To calculate the probability that a randomly selected male will have a foot length between 8 and 12.5 inches, we first calculate the z score for 8 inches and then for 12.5 inches.
For 8 inches:

For 12.5 inches:

From the normal distribution table, The probability that a randomly selected male will have a foot length between 8 and 12.5 inches = P(8 < x < 12.5) = P(-2 < z < 1) = P(z < 1) - P(z < -2) = 0.8413 - 0.0228 = 0.8185 = 81.85%
Step-by-step explanation:
4 x 6 = 24 (side1)
8 x 4 = 32 (side2)
6 × 8 = 24 (side3)
6 x 8 = 24 (side4)


4 x 10 = 40 (side5)
surface area = 24 + 32 + 24 + 24 + 40 = 144ft squared
Answer:
There are 10 boys and 6 girls in the class
Step-by-step explanation:
The given parameters are;
The number of boys = The number of girls + 4
The number of students in the class = 16
Let x represent the number of girls in the class and let y represent the number of boys in the class
Therefore;
y = x + 4...(1)
x + y = 16...(2)
Making y the subject of equation (2) gives;
y = 16 - x
Equating the values of y from equation (1) and equation (2) gives;
x + 4 = 16 - x
Which gives;
2·x = 16 - 4 = 12
x = 12/2 = 6
x = 6
The number of girls = x = 6
From equation (1), we have;
y = x + 4 = 6 + 4 = 10
y = 10
The number of boys = y = 10.
Answer:
This a test?
Step-by-step explanation:
y = 90°
Solution:
The reference image for the answer is attached below.
The sum of opposite interior angles is equal to the exterior angles.
m∠BAC + m∠ACB = 110°
m∠BAC + 70° = 110°
m∠BAC = 110° – 70°
m∠BAC = 40°
m∠BAD + m∠DAC = 40°
x + x = 40°
2x = 40°
Divide by 2 on both sides of the equation.
x = 20°
In triangle DAC,
Sum of all the angles of a triangle = 180°
m∠DAC + m∠ACD + m∠CDA = 180°
20° + 70° + m∠CDA = 180°
90° + m∠CDA = 180°
m∠CDA = 180° – 90°
m∠CDA = 90°
∠CDA and y lies on the straight line. So they form a linear pair.
y + m∠CDA = 180°
y + 90° = 180°
y = 180° – 90°
y = 90°
The value of y is 90°.