The probability that Rehan will be able to solve a certain problem is 1/5. That Shoaib will be able to solve is 1/4. If both boys work separately on the problem the probablity that both will solve it is ?

a)1/10 b)1/5 c)1/20 d) 1/4

Question

The probability that Rehan will be able to solve a certain problem is 1/5. That Shoaib will be able to solve is 1/4. If both boys work separately on the problem the probablity that both will solve it is ?

a)1/10   b)1/5     c)1/20   d) 1/4

shubhamsrg · Answer

Shouldn't the question be finding probability that the problem will be solved ?
and not that "both will solve it" ?

anonymous · Answer

no that is the ques!

shubhamsrg · Answer

then I guess it should simply be P(shoaib solving it) * P(rehan solving it)

we multiply here coz we want both events to occur simultaneously

anonymous · Answer

ok so hum probalities add akb karte hain?

shubhamsrg · Answer

jab alag alag cases ho..
jaise agar ques ho ki problem solve ho jaye exactly kisi bhi 1 se
then hoga P(R solving it)*P(S not solving it) + P(R not solving it) * P(S solving it)

hope you follow

anonymous · Answer

ok thanks :)