Microsoft Office Tutorials and References

In Depth Information

**Syntax**

What if you are allowed to repeat a choice? Say that you are ordering three

scoops of ice cream. You can choose chocolate, chocolate, chocolate. Or

you can choose two chocolate and one peppermint. If you had to choose three

scoops from five flavors of ice cream, you might think you have 5 × 5 × 5, or

125 combinations.

However, order does not matter in the ice cream bowl
—
chocolate, chocolate,

peppermint is the same a chocolate, peppermint, chocolate. Microsoft added

=COMBINA() to handle this scenario. As shown in C14 of
Figure 11.26
, there

are really only 35 combinations of three scoops of ice cream.

Syntax

=COMBIN(number, number_chosen)

Syntax

=COMBINA(number, number_chosen)

These functions return the number of combinations for a given number of

items. COMBIN assumes repeats are not allowed. COMBINA allows for re-

peats. These functions require two arguments:

•
numberis the total number of items.

•
number_chosenis the number of items in each combination.

Using

Using
FACT

to Calculate the Permutation of a Number

Suppose you have seven slides in a PowerPoint presentation. Furthermore,

you want to find the number of unique sequences in which the slides can be ar-

ranged; this is called the factorial of seven. You calculated this by using

7 × 6 × 5 × 4 × 3 × 2 × 1. To find the factorial of any positive integer, you use the

FACT function.

FACT
to Calculate the Permutation of a Number

Syntax

=FACT(number)

The FACT function returns the factorial of a number. The factorial of a

number is equal to 1 × 2 × 3 × ... × number. numberis the nonnegative number of

which you want the factorial. If numberis not an integer, it is truncated.