<p>It’s gotta be SD = 5. Standard deviation is trigonal, which means that it depends on the squares of the two constituent standard deviations, and not just the difference between them. So like you said, it’s sqrt(9+16)</p>
<p>It’s gotta be SD = 5. Standard deviation is trigonal, which means that it depends on the squares of the two constituent standard deviations, and not just the difference between them. So like you said, it’s sqrt(9+16)</p>