Mixing E85 and Pump Fuel

How would you find the stoichiometric value for mixing E85 and pump fuel. The example I am using is running an E30 blend (30percent E85 and 70percent Pump Fuel). Would I take E85 value of 9.8 and divide by .3, and divide pump fuel's value of 14.7 by .7 and add them to together. Something like this: (9.8/.3) + (14.7/.7) = 13.23. Could the same be applied to other percentages of mixing E85 (E40, E50,etc.). Any input would be greatly appreciated.

9.8/.3=2.94

14.7/.7=10.29

2.94+10.29=13.23

it is a linear scale not sure on the math but it looks right to me

Regards Ross

You would read Lambda 1.0.

If your wideband has the AFR scaled at 14.7 = Lambda 1.0, then it would read 14.7 regardless of the fuel composition at the stoichiometric value.