Error using * Inner matrix dimensions must agree.

I have inputted the following code and continue to get the error

Error using  * 
Inner matrix dimensions must agree.

Error (line 16)
mprop1=mpay1*(exp(f1*DeltaV1/vex1 )-1)*(1-finert1 )/(1-finert1*exp(DeltaV1/vex1 ) );

I am not sure where the mistake is any help would be appreciated

g=9.81;
Isp1=290;
Isp2=295;
vex1=g*Isp1;
vex2=g*Isp2;
finert1=0.095;
finert2=0.1;
finert3=0.105;
DeltaV=9000;
f1=linspace(0,1);
DeltaV2=(1-f1)*DeltaV;
DeltaV1=f1*DeltaV;
mpay2=1400
mpay1=50000
mprop2=mpay2*(exp((1-f1).*DeltaV2./vex2 )-1)*(1-finert2)/(1-finert2*exp(DeltaV2./vex2 ) );
mprop1=mpay1*(exp(f1*DeltaV1/vex1 )-1)*(1-finert1 )/(1-finert1*exp(DeltaV1/vex1 ) );
plot(mprop2,f1)

Answer 1

[Torsten]

mprop2=mpay2*(exp((1-f1).*DeltaV2/vex2 )-1)*(1-finert2)./(1-finert2*exp(DeltaV2/vex2 ) );

mprop1=mpay1*(exp(f1.*DeltaV1/vex1 )-1)*(1-finert1 )./(1-finert1*exp(DeltaV1/vex1 ) );

(if this is really what you want)

Best wishes

Torsten.