Just change the name of the column based on which you have to group and name of the column of the price to get the Sum. Use the below query in Assign activity
Dictionarty=( From p in dta.Select
group p by Department=p.Item("PRODUCT") Into GroupA=Group
Select GroupA).ToDictionary(Function(x) x(0)("PRODUCT").ToString, Function(x) Convert.ToString(x.Sum(Function(y) Convert.ToDouble(y.Item("PRICE").ToString))))
Dictionary is the variable of Dictionary(Of string, String)
dta is your Excel Sheet, stored in a datatable by using Read Range Activity.
Now you can access the the total sum of the product by like this
Dictionary(“Mobile”) to get the total sum of price of mobile category. and it will return 7000 as per your Example.