The quantities of orange supplied by a producer in a week is shown below 12,6,7,3,15,10,18,9 calculate the variance deviation for groupdata and ungroupdata.

To calculate the variance and standard deviation for the given data, we need two sets of calculations: one for grouped data and another for ungrouped data.

1. Ungrouped data:
a) Calculate the mean (average) by adding up all the individual values and dividing by the number of values.
Mean = (12 + 6 + 7 + 3 + 15 + 10 + 18 + 9) / 8 = 80 / 8 = 10

b) Calculate the deviation of each value from the mean by subtracting the mean from each value.
Deviation = (12 - 10, 6 - 10, 7 - 10, 3 - 10, 15 - 10, 10 - 10, 18 - 10, 9 - 10)
= (2, -4, -3, -7, 5, 0, 8, -1)

c) Square each deviation to eliminate negative values.
Squared Deviation = (2^2, (-4)^2, (-3)^2, (-7)^2, 5^2, 0^2, 8^2, (-1)^2)
= (4, 16, 9, 49, 25, 0, 64, 1)
= (4, 16, 9, 49, 25, 0, 64, 1)

d) Calculate the variance by taking the average of the squared deviations.
Variance = (4 + 16 + 9 + 49 + 25 + 0 + 64 + 1) / 8 = 168 / 8 = 21

e) Calculate the standard deviation, which is the square root of the variance.
Standard Deviation = sqrt(21) ≈ 4.5826

2. Grouped data:
a) To calculate the variance and standard deviation for grouped data, we first need to determine the midpoints of each class interval. However, the given data doesn't provide any class intervals. If you have class intervals mentioned, please provide them to proceed with the calculation.

In summary, for the given ungrouped data, the variance is 21 and the standard deviation is approximately 4.5826. However, without class intervals, it is not possible to calculate the variance and standard deviation for grouped data.