Find the variance and standard deviation 10 - 19 5 20-29 11 30 -39 7 40-49 3 50-59 8 please show me the step .. Thank you

The answer is b) 32 your welcome

Period is the time it takes for one “cycle” to complete. in the parent sine function, period is 2*pi since sin(0) = 0, sin(pi/2) = 1, sin(pi) = 0, sin(3pi/2) = -1, and sin(2pi) = 0. at that point, the sequence repeats itself. i’m not sure if your graph is similar to the sine function since you didn’t provide a picture, but you can find the period by looking at a graph.