Suppose a brand of light bulbs is normally distributed, with a mean life of 1800 hr and a standard deviation of 150 hr.
|
Areas Under the Standard Normal Curve
|
|
z
|
A
|
Z
|
A
|
|
1.00
|
.3413
|
1.50
|
.4332
|
|
1.10
|
.3643
|
1.60
|
.4452
|
|
1.20
|
.3849
|
1.70
|
.4554
|
|
1.30
|
.4032
|
1.80
|
.4641
|
|
1.40
|
.4192
|
1.90
|
.4713
|
Find the probability that a bulb of the brand lasts between 1515 hr and 2010 hr.