MMULT (Returns the matrix product of two arrays)

What Does It Do?

This function multiplies one range of values with another range of values.

The ranges do not have to be of equal size.

The dimensions of the result range is in direct proportion to dimensions of the two input ranges.

It is an Array function and must be entered using the Ctrl+Shift+Enter combination.

Syntax

=MMULT(Range1,Range2)

Formatting

No special formatting is needed.

Example

The following tables were used by a company producing boxes of chocolates.

The types of chocolate produced were Milk, Dark and White.

The company boxed the chocolates in three differing mixtures of Milk, Dark and White.

In the run up to Christmas customers ordered various quantities of each box.

The chocolate company now needed to know what quantity of each type of chocolate to produce.

The =MMULT() function was used to multiply the contents of boxes by the customer orders.

The result of the =MMULT() is the total number of each type of chocolate to produce.

How It Was Done

Cells C36 to E36 were selected.

The formula =MMULT(C32:E32,C26:E28) was typed, (but not yet entered).

The keys Ctrl+Shift+Enter were pressed to confirm the entry as an array.

The formula then showed the correct result.

Getting The Dimensions Correct

The dimensions of the Result range are directly related to the two input ranges.

The number of rows in the Result should be equal to the rows in Range1.

The number of columns in the Result should be equal to the columns in Range2.

Example

The following tables were used by the chocolate company to calculate the amount of ingredients needed to produce batches of chocolate.

The company has four factories, each of which has to order enough Butter, Eggs and Sugar to ensure they can meet production targets.

Range 1 contains the planned production of Milk and Dark chocolate for each factory.

Range 2 contains the amount Butter, Eggs and Sugar needed to make 1 unit of Milk or Plain.

The Result range shows the quantities of each ingredient that will have to be ordered to meet the production target.

Note the depth of the Result is the same as the depth of Range 1, and the width of the Result is the same as the width of Range 2.

Hint

To get a feel for how the =MMULT() function operates, set all values in Range1 and Range2 to zero 0, then change a single value in each.