Calculate a weighted average

To do this task, use the SUMPRODUCT and SUM functions.
This example calculates the average price paid for a unit across three purchases, where each purchase is for a different number of units at a different price per unit.

	A	B
	Price per unit	Number of units
1	20	500
2	25	750
3	35	200
	Formula	Description (Result)
	=SUMPRODUCT(A2:A4,B2:B4)/SUM(B2:B4)	Divides the total cost of all three orders by the total number of units ordered (24.66)

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Excel Cell Formating

Today I would like to present you some tips on excel formatting; 1. Formatting an excel cell to Text, Number, Date , Time, Currency, Accounting, special or custom.         Select any excel cell and then on the menu click on Format then click on cell you can also use shortcut to open the cell formatting box directly by holding Ctrl+1 key, as shown in the following figure.    As in the above figure you can see Category box from where you can change the cell format to your desired format. You can do lot more than format in an excel cell. Make your excel cell a digital clock or digital image viewer, whatever you want just imagine and do it by using all the advanced features of cell formatting  to know more about how to do it just give a comment to this post.