m really sorry for doing my meaningless comment .now i got my answer very clearly m really so sorry for this mistake...
sir aapne video me wrong answer likha h rate of apearance k liye
sir why we don't put rate2 in case of rate of appearance
Sir in 05:25 jase appne o.o.r with respect to A separate nikale vese he o.o.r with respect to B seprate kyo ni nikale means at 05:25 why u take A also to find o.o.r of B
sir how can i solve this problem.