The syntax of the function Choose is as follow

CHOOSE(index, value1, … value30)

Uses an index to return a value from a list of up to 30 values. Index is a reference or number between 1 and 30 indicating which value is to be taken from the list. Value1, … value30 is the list of values entered as a reference to a cell or as individual values.

CHOOSE can return a value or a range from a list of 1 to 30 arguments.

When the “lookup_value” / index_number is whole number between 1 and 30, CHOOSE can be a good lookup tool

If index_num is 1, then value1 is used …

If index_num is 2, then value2 is used

value can be a number, or a formula/function, “text” (in quotes), a range, cell references, or defined names

To find next friday from any given day we can use Choose function

Suppose A1 hold the 1/1/2012 (mm/dd/yyyy)

the following formula will give the next friday

=CHOOSE(WEEKDAY(A1),A1+5,A1+4,A1+3,A1+2,A1+1,A1,A1+6,A1+7)

if we have data down as below

The formula in cell D2 is

=CHOOSE(C3,”SUM”,”COUNT”)

if the cell C3 is 1 we will get SUM and if cell C3 is 2 we will get COUNT

The formula in cell D3 is

=CHOOSE(C3,SUM(A1:A5),COUNT(A1:A5))

In the example shown above the cell C3 is 2 so we will get the count of cells from A1 TO A5

if the cell value in C3 is 1 we will get the SUM of cells from A1 to A5