Answer:
Explanation:
Hello!
X: voltage, it has a mean of μ= 118.5V and a standard deviation of σ= 1.20V.
Assuming the variable has a normal distribution, I'll use the standard normal distribution to calculate the probability that the voltage is between 116 and 120 volts.
P(116≤X≤120) = P(X≤120) - P(X≤116)
Using Z= (X - μ)/σ you now standardize the voltage values and get the cumulative probabilities from the tables of Z.
P(Z≤(120-118.5)/1.20) - P(Z≤(116-118.5)/1.20)
P(Z≤1.25) - P(Z≤-2.08)= 0.89435 - 0.01876= 0.87559
87.559% of the data will be between 116 and 120 volts.
I hope you have a SUPER day!