Conditional Formatting based on two cells, output in a third.

Maybe conditional formatting won't help at all. Please don't mind the English as I have translated. Also this is what was given me by my MIL to help. 

So I have this grading sheet where I have two grades (B and D). 

The rules is basically

if B =>70 -- approved
if B =<70 -- failed

The output is on C.

Same with column D, output is on E. 

Ignoring F, I need help with column G.

G is for Final aprove or Fail. 

To be approved, both B and D have to have a value of =>70. If even just one is less than 70, it's considered a fail.

I basically have 200 rows to take care of, I tried conditional formatting by creating 4 rules but basically they cancelled themselves out. And even then, I could not also make the output to be APPROVED or FAIL. Remembered is only cell format, but even then. 

The formulas I tried on column G

=$B3=>70 -- green
=$B3=<70 -- red

=$D3=>70 -- green
=$3D=<70 -- red

--

Apreciate any help, m y