In this section, you will find a step by step to use the formula aggregation concept.

Create a formula on Ritchie that will **execute another formula inside it.**

You'll find all the informations you need in the

how to group formulastutorial section.

**
**The idea is to group at least 2 formulas inside another one:

(Level 1)**rit math sum numbers**

(TODO)**rit math multiply numbers**

Command suggestion: `rit math calculate`

This formula needs to contain (at least) those three inputs parameters:

Number one (

`RIT_UMBER_ONE`

).Number two (

`RIT_NUMBER_TWO`

).Operation (

`RIT_OPERATION`

).

To implement this formula, it will be necessary to follow the steps below:

**Premisse: **Creation of the

formula (same as level 1).**rit math multiply numbers**

Extract all inputs parameters.

Execute the grouped formula according to the selected operation:

**multiply**should call**rit math multiply numbers****sum**should call**rit math sum numbers**â€‹

Return the result on the terminal.

If you want to play a little more, here are some suggestions:

Add more operations.

Add the option to inform any quantity of numbers as inputs.