Answer:
Third quartile (Q₃) = 46.75 minutes.
Therefore, Option (c) is the correct answer.
Step-by-step explanation:
Given: Mean (μ) = 40 minutes and S.D (σ) = 10 minutes
To find : Third quartile (Q₃) = ?
Sol: As the third quartile of normal distribution covers the 75% of the total area of the curve and first quartile covers the 25% of the total area of the curve. Then with the help of z score table, the value represented the third quartile of the normal distribution is:
Q₃ = μ + 0.675 σ
Now by substitution the value of mean and standard deviation,
Q₃ = 40 + 0.675 × (10)
Q₃ = 40 + 6.75
Q₃ = 46.75
Therefore, the third quartile (Q₃) = 46.75. So, option (c) is the correct answer.
5353 minutes = 89.22 hours
Maybe the figures should be 53 and 20??
Let's let Billy = A
The formula to use for work problems is
Time = (A*B) / (A+B)
53 = ( (A +20)* A) / (A +20 + A) )
53 = ( A^2 + 20A ) / (2A + 20)
A^2 + 20A -106A -1060
A^2 -86A -1060
A = 96.935
Bobby Mows in 116.935 minutes
Answer: 28/r+4
Step-by-step explanation: Divide each term by r + 4 and simplify
Answer:
Step-by-step explanation:
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