The diameters of bolts produced by a certain machine are normally distributed with a mean of 0.30 inches and a standard deviation of 0.01 inches. What is the probability of selecting a bolt at random that has a diameter larger than 0.328 inches

The probability of selecting a bolt at random that has a diameter larger than 0.328 inches is 0.00256.

Step-by-step explanation:

We are given that the diameters of bolts produced by a certain machine are normally distributed with a mean of 0.30 inches and a standard deviation of 0.01 inches.

Let X = diameters of bolts produced by a certain machine

SO, X ~ N()

The z-score probability distribution is given by ;

                 Z = ~ N(0,1)

where, = mean diameter = 0.30 inches

            = standard deviation = 0.01 inches

The Z-score measures how many standard deviations the measure is away from the mean. After finding the Z-score, we look at the z-score table and find the p-value (area) associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X.

Now, the probability of selecting a bolt at random that has a diameter larger than 0.328 inches is given by = P(X > 0.328 inches)

    P(X > 0.328) = P( > ) = P(Z > 2.80) = 1 - P(Z 2.80)

                                                            = 1 - 0.99744 = 0.00256

The above probability is calculated using z table by looking at value of x = 2.80 in the z table which have an area of 0.99744.

Therefore, probability of selecting a bolt at random that has a diameter larger than 0.328 inches is 0.00256.

see explanation

step-by-step explanation:

a

(6r + 7) + (13 + 7r) ( remove brackets and collect like terms )

= 6r + 7 + 13 + 7r

= 13r + 20

b

remove brackets and collect like terms

13 - r - 1 + r

= 12 - r

c

remove brackets and collect like terms

= - 8 - r + 2r - 4

= - 12 + r

d

remove brackets and collect like terms

= 7r - - - 6r

[-   - = - - = - ]

= r -