Answer:
a) 0.997 is the probability that the breaking strength is at least 772 newtons.
b) 0.974 is the probability that this material has a breaking strength of at least 772 but not more than 820
Step-by-step explanation:
We are given the following information in the question:
Mean, μ = 800 newtons
Standard Deviation, σ = 10 newtons
We are given that the distribution of breaking strength is a bell shaped distribution that is a normal distribution.
Formula:
a) P( breaking strength of at least 772 newtons)
Calculation the value from standard normal z table, we have,
0.997 is the probability that the breaking strength is at least 772 newtons.
b) P( breaking strength of at least 772 but not more than 820)
0.974 is the probability that this material has a breaking strength of at least 772 but not more than 820.