I don’t understand this can someone pls help me with it

Aparallel system functions whenever at least one of its components works. consider a parallel system of n components, and suppose each component works independently with probability 0.5. find the conditional probability that component n works given that the system is working

Solve - pv + 40 < 65 for v solve 7w - 3r = 15 for r

Yosef can eat 21 jamuns while rose can eat just 15 . complete the blank. yosef can eat % more jamuns than rose.