what method did u use to get 1.21?
i cant believe i got this right, i full skipped it then went back to it in the last 3 mi utes and just bullshitted hoping to get some marks, but ended up bullshitting the correct answer!! haha
anywho this is how i did it, i made a tree diagram, then worked out all the sample spaces and there percentages, which were {RRR} {RRS} {RSR} and {RSS}. i then multiplied the each of the sample space percentages by how many S's were in them, so for {RRR} i did 0x.45x.45, for {RRS} i did 1x.45x.55, for {RSR} i did 1x.55x.25 and for {RSS} i did 2x.55x.75 and wallah!! the answer spat out 1.21 which seems to be correct.
im doubting that is the correct way to work it out as i just bullshitted using common logic but yeh, fuckin sickkk!!