Answer: 61,750 miles
Step-by-step explanation:
Given : The p-value of the tires to outlast the warranty = 0.96
The probability that corresponds to 0.96 from a Normal distribution table is 1.75.
Mean : 
Standard deviation : 
The formula for z-score is given by : -

Hence, the tread life of tire should be 61,750 miles if they want 96% of the tires to outlast the warranty.
Answer:
Step-by-step explanation:
<u>We have:</u>
- p = -1/5x + 100 = -0.2x + 100
a) <u>The revenue is:</u>
- R = px
- R = x( -0.2x + 100)
- R= -0.2x² + 100x
b) <u>x = 200, find R:</u>
- R = -0.2(200²) + 100(200) = 12000
c) <u>This is a quadratic function and the maximum value is obtained at vertex.</u>
- x = -100/(-0.2*2) = 250 is the required quantity
d) <u>The max revenue is obtained when -0.2x + 100 at max:</u>
- The maximum possible is p = 100 when x = 0
Since only one person can finish in first place, one in second, etc., the total number of placers is 12x11x10, or 1320 different ways the 12 racers can finish 1st, 2nd and 3rd....
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