If two dice are thrown simultaneously,what is the probability of getting $1$ on the first die?

The chances to fail in Physics are $20\%$ and the chances to fail in Mathematics are $10\%$. What are the chances to fail in at least one subject? ............ $\%$

In a set of $30$ game cards,$17$ are white and the rest are green. Out of $30$,$4$ white and $5$ green cards are marked $IMPORTANT$. If a card is chosen randomly from this set,then the probability of choosing a green card or an $IMPORTANT$ card is:

$A$ six-faced unbiased die is thrown twice and the sum of the numbers appearing on the upper face is observed to be $7$. The probability that the number $3$ has appeared at least once is:

Given $P(A \cup B)=0.6$ and $P(A \cap B)=0.2$,the probability that exactly one of the events occurs is:

Two dice are thrown simultaneously. What is the probability of obtaining a sum of the numbers less than $11$?