Answer
Answer: 0.00235
Work Step by Step
Want to find P( z < -2.825)
1) -2.825 is between z = -2.820 and z = -2.830, so we have to find:
P ( z < -2.82) = 0.0024
P(z < -2.83) = 0.0023
2) We take the average of the first two probabilities we found above:
(0.0024 + 0.0023)/2 = 0.00235