Andy is learning to play the guitar. last week he recorded the minutes per day that he practiced. find the mean absolute deviation. round to the nearest tenth.
day s m t w t f s
minutes 40 55 35 60 20 50 55

Step-by-step explanation:

The means absolute deviations is define by:

From the formula, we observe that we need to find the mean, and then find the different between that mean and each element. Then, we have to sum all those differences and divide this by the total number of elements.

So, the mean is

Now, each difference would be

The sum of all differences, using their absolute value, would be:

Then, we divide this result by the total number of elements which is 7:

Therefore, the mean absolute deviation is approximately is 11.43.

x = ± 6i

step-by-step explanation:

x^2 = -36

take the square root of each side

sqrt(x^2) = sqrt(-36)

we know sqrt(ab) = sqrt(a) sqrt(b)

x = ±sqrt(36) sqrt(-1)

we know that sqrt (-1) = i

x = ± 6i