You didn’t add a screenshot. I’m sorry for answering but someone else will if I don’t.
On your calculator, use the normalcdf() function, enter the Lower Limit, Upper Limit, Mean, and Standard deviation.
The mean and standard deviation are given to you. You want to find "less than 13.5 seconds", meaning that 13.5 is the maximum "Upper Limit" and 0 would be the Lower Limit because we can pretend 0 second is the minimum. Don't worry about negatives, in this scenario, values like "-5 seconds" are impossible.
Enter normalcdf(0, 13.5, 13.56, 2.24) in a calculator and the output result is the answer.
It depends on how fast it was thrown/kicked but the average is around 9/10
<span>2500+150x=3000+125x
150x-125x=3000-2500
25x=500
</span><span>x=500/25
x=20 mo
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2500+150*20=3000+125*20
5500=5500 total paid after each month.</span><span>
</span>
