different major products formed why?

srry... forgot...
"there's no use of asking the questions here..." :P

well the answer is probability factor...

for cl , 1 degree : 2 degree : 3 degree - 1 : 3 : 5.8
for br, 1 degree : 2 degree : 3 degree - 1 : 80 : 1600

got the answer from one of my friends

Could you answer the cause or such degree of variation in the Probability factor?

no...