Hi there,
If you know the percentage of revenues of each division, you should be able to get it by multiplying the gross margin of each division times the percentage of contribution of revenues of that particular division out of the total.
Example:
- Division A
- Gross profit: 10
- Revenues: 20
- Margin: 50%
- Division B
- Gross profit: 15
- Revenues: 20
- Margin: 75%
- Division C
- Gross profit: 20
- Revenues: 50
- Margin: 40%
Total revenues are 90.
You can get the overall margin as:
50%*(20/90)+75%*(20/90)+40%*(50/90) =50%
Indeed you can check we get the same result as calculating the overall company gross margin:
- Overall
- Gross profit: 45
- Revenues: 90
- Margin: 50%
Hope this helps,
Francesco