l Normal Distribution Calculator
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Answer
P(x<-1.401) = 0.080757


Steps Explained:

Given X = 240, μ = 250, and σ = 7.14

Calculate P(X < Z)

Z-score formula

Using the Normal Distribution, Calculate P(X < 240)

Z  =  X - μ
  σ/√1

Z  =  240 - 250
  7.14/√1

Z  =  -10
  7.14/1

Z  =  -10
  7.14

Z = -1.401

From the table below, we see that our Z value is = 0.419243

Z-table Lookup Value

The z-table probability runs from 0 to z and -z to 0

Z value = 0.419243

Since that represents ½ of the graph, we subtract our value from 0.5 → 0.5 - 0.419243

P(x<-1.401) = 0.080757

Final Answer

P(x<-1.401) = 0.080757

Related Calculators:  Negative Binomial Distribution  |  Geometric Distribution  |  Binomial Distribution