Open Need some help with a math formula

I am trying to setup a test that will take two verables I've setup. One is the room temperature from my Arduino and the other is the relative humidity from the same Arduino.
I've found a formula to get a feels like temperature but when I input it into Tasker I get told I'm am not doing something right.
Here is the formula.
0.5*{%Avg+61.0+[(%Avg-68.0*1.2]+(%RH1*0.094)}
The %Avg is my Temperature verable and the %RH1 is the Relative Humidity.
Now here is what Tasker is telling me.

17.46.27/Variables doreplresult: |%RH2| -> |159.224|
17.46.27/Variables doreplresult: |0.5*{%Avg+61.0+[(%Avg-68.0*1.2]+(%RH1*0.094)| -> |0.5*{80.4+61.0+[(80.4-68.0*1.2]+(0.25*0.094)|
17.46.27/E Variable Set: %RH2 -> %RH2
17.46.27/Variables doreplresult: |0.5*{%Avg+61.0+[(%Avg-68.0*1.2]+(%RH1*0.094)| -> |0.5*{80.4+61.0+[(80.4-68.0*1.2]+(0.25*0.094)|
17.46.27/Expr mathEval: 0.5*{80.4+61.0+[(80.4-68.0*1.2]+(0.25*0.094): dsv/Variable Set/0.5*{%Avg+61.0+[(%Avg-68.0*1.2]+(%RH1*0.094): Mathematical expression contains the invalid value "{80.4" at offset 4 in expression "0.5*{80.4+61.0+[(80.4-68.0*1.2]+(0.25*0.094)"
17.46.27/E Variable Set: %RH2: failed, not numeric ?
17.46.27/E result: stop task (error)
17.46.27/Variables doreplresult: |%RH2| -> |159.224|
17.46.27/E Error: 1
17.46.27/MacroEdit action finished exeID 123 action no 1 code 547 status: Err next 1
Any help with getting this to work would be great thanks.

As and update I removed the {} and [] and replaced them with () and tasker works with that but the number it comes up is way to low then it should be all most 10 to 12 degrees.