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diff --git a/3760/CH4/EX4.68/Ex4_68.sce b/3760/CH4/EX4.68/Ex4_68.sce
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+clc;
+v=250; // rated voltage of shunt motor
+p=15000; // rated power of motor
+nm=0.88; // maximumu efficiency of motor
+n=700; // speed of motor
+rf=100; // resistance of shunt field
+i=78; // current drawn by mains
+f=0.8; // fraction of rated output being delivered
+l=((1/nm)-1)*f*p; // total losses
+// at maximum losses constant losses= variable losses
+lc=l/2; // constant losses
+pi=f*p+l; // input to motor at maximum efficiency
+il=pi/v; // input line current
+ia=il-(v/rf); // armature current
+ra=lc/ia^2; // armature resistance
+ia2=i-(v/rf); // armature current at given load 
+pi=i*v; // total power input
+tl=ia2^2*ra+lc; // total losses
+n1=(1-(tl/pi))*100; // efficiency at line current of 75 A
+Ea1=v-ia*ra; // counter EMF
+Ea2=v-ia2*ra; // counter EMF corresponding to line current of 75 A
+// field current is constant so flux is constant
+n2=(Ea2/Ea1)*n;
+printf('Efficiency at line current of %d A is %f percent\n',i,ceil(n1));
+printf('Speed at line current of %d A is %f rpm',i,floor(n2));