Select both the 2nd and 4th options!
A negative exponent just means that the base is on the wrong side of the fraction line, so you need to flip the base to the other side.
For example

or

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The answer is "D"
Solution :
Given data :
The mean length of the steel rod = 29 centimeter (cm)
The standard deviation of a normally distributed lengths of rods = 0.07 centimeter (cm)
a). We are required to find the proportion of rod that have a length of less than 28.9 centimeter (cm).
Therefore, P(x < 28.9) = P(z < (28.9-29) / 0.07)
= P(z < -1.42)
= 0.0778
b). Any rods which is shorter than
cm or longer than
cm that re discarded.
Therefore,
P (x < 24.84 or 25.16 < x) = P( -59.42 < z or -54.85)
= 1.052
Line 5 shows the division property of equality.
The division property of equality states that you can divide both sides of the equation by the same number and the equation remains the same. This equation is being divided by 4 on both sides.