Answer: 120.9
Step-by-step explanation: 65% of 186 is 120.9.
First, determine the z-score of 675.
z = (675 - 500) / 100 = 1.75
The z-score of 500 is,
z = 0.
Subtracting the z-scores will give us 1.75. This is equal to 0.9599.
= 0.9599 - 0.5 = 0.4599
Multiplying this to the given number of light bulbs,
n = 0.4599 x 5000 = 2299.5
Therefore, there is approximately 2300 light bulbs expected to last between 500 to 675 hours.
Step-by-step explanation:
sinx = a/b
tanx= a/c
cosx= c/b