# Question: 1athere are approximately one billion smartphone users in the world...

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1aThere are approximately one billion smartphone users in the world today. In the United States, the ages of smartphone users between 13 to 55 approximately follow a normal distribution with approximate mean and standard deviation of 37 years and 8 years, respectively.Using the 68-95-99.7 Rule, what percent of smartphone users are greater than 53 years old?

bThere are approximately one billion smartphone users in the world today. In the United States, the ages of smartphone users between 13 to 55 approximately follow a normal distribution with approximate mean and standard deviation of 37 years and 8 years, respectively. Using the 68-95-99.7 Rule, what percent of smartphone users are between 29 and 53 years old?