Question about queries for a panel

Hi there, I am trying to calculate a value for a status panel. I have the metrics I need but cannot make the calculation.

Queries are as follow:

Query B counts number of value with timeframe (hidden)
Query C sum’s the value within same timeframe (hidden)
I’d like next query to divide query C in B. IE: C / B = (next query letter D) (shown)

I’d like the Status Panel to show percentage of service availability…

Any suggestion?