Five horses are in a race. $Mr. A$ selects two of the horses at random and bets on them. The probability that $Mr. A$ selected the winning horse is

The coefficients $a, b$ and $c$ of the quadratic equation $ax^{2} + bx + c = 0$ are obtained by throwing a die three times. The probability that this equation has equal roots is

Let $S$ be the set of all the words that can be formed by arranging all the letters of the word $\text{GARDEN}$. From the set $S$,one word is selected at random. The probability that the selected word will $\text{NOT}$ have vowels in alphabetical order is:

If out of $20$ consecutive whole numbers two are chosen at random,then the probability that their sum is odd,is

In a relay race there are five teams $A, B, C, D$ and $E$. What is the probability that $A, B$ and $C$ finish first,second and third,respectively?

$A$ box contains $5$ blue and $4$ white chalks. If two chalks are chosen at random,what is the probability that both chalks are of the same color?