The mean is just the multiplication of [tex]n[/tex] and [tex]p[/tex] so [tex]60 * 0.3[/tex] = [tex]18[/tex]
Variance is [tex](1 - p) * n * p[/tex] so [tex]0.7 * 60 * 0.3 = 12.6[/tex]
So the variance is [tex]12.6[/tex]
The standard deviation is just the root of the variance so: [tex]\sqrt{12.6}[/tex] = [tex]3.55[/tex] rounded to the nearest hundredth. :D
