Answer:
0.3114
Option d is right
Step-by-step explanation:
Let X be the time spent on a treadmill in the health club
Given that research shows that on average, patrons spend an average of 42.5 minutes on the treadmill, with a standard deviation of 5.4 minutes
Also given that X is normal
the probability that randomly selected individual would spent between 30 and 40 minutes on the treadmill.
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round off to two decimals tog et
the probability that randomly selected individual would spent between 30 and 40 minutes on the treadmill is 0.31
Hence option d is right
(a+b)^7= a^7+ 7a^7b+ 21 a^6b²+ 35a^5b³+ 35 a⁴b⁴+ 21 a³b^5 + 7a²b^6 + b^7
Answer:
18
Step-by-step explanation:
Hope this helps!