the following data represents the price(R) of 50 items purchaced by a shopper. price(R) 0.00<20.00, 20.00<40.00, 40.00<60.00, 60.00<80.00, 80.00<100.00. frequently 6, 9, 18, 13, 4. Determine with calculations:

a) mean price
b)median price
c)modal price
d)standard deviation
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