How do I sum two metrics in grafana with influx?

InfluxDB 2 Dashboards
1

InfluxDB shell version: 1.7.6

Grafana v6.2

I made two queries in grafana to pull data from pfsense. bytes sent and bytes received. Well now I want to display a 3rd bar that adds both of those together. How do I go about doing this?
Any help appreciated. People keep saying use sumseries but I cant make sense of it in any of the posts I find on google.

Series A:

SELECT last(“bytes_recv”) /1078114354 FROM “net” WHERE (“interface” = ‘vtnet0’) AND timeFilter GROUP BY time(__interval) fill(null)

Series B:

SELECT last(“bytes_sent”) /1209270754 FROM “net” WHERE (“interface” = ‘vtnet0’) AND timeFilter GROUP BY time(__interval) fill(null)

What will series c look like?

2

you can use something like this.

SELECT “last(“bytes_recv”) /1078114354” + “last(“bytes_sent”) /1209270754” FROM “net” WHERE (“interface” = ‘vtnet0’) AND timeFilter GROUP BY time(__interval) fill(null).