steps
(x) = 5x^2-3x+7
refine
x=5x^2-3x+7
Switch sides
5x^2-3x+7-x=x-x
Subtract x from both sides
5x^2-4x+7=0
Solve with the quadratic formula
2/5 because if you subtract 5/5 of 3/5 it will give you 2/5
Answer:
The probability of a bulb lasting for at most 606 hours is 0.9032
Step-by-step explanation:
The mean lifetime of a bulb is 580 hours.
The standard deviation of the lifetime is 20 hours
We are supposed to find the probability of a bulb lasting for at most 606 hours i.e.
Formula :
Z=1.3
Refer the z table
Hence the probability of a bulb lasting for at most 606 hours is 0.9032
W=-3 if you need any other help just message me