A pair of dice is thrown and the sum of the numbers appearing on the dice is observed to be 7 . Find the probability that the number 5 has appeared on atleast one die.
OR
The probability that $\mathrm{A}$ hits the target is $\frac{1}{3}$ and the probability that $\mathrm{B}$ hits it, is $\frac{2}{5}$. If both try to hit the target independently, find the probability that the target is hit.