In a box,there are $8$ red,$7$ blue and $6$ green balls. One ball is picked up at random. What is the probability that it is neither red nor green?

In a college,$25\%$ of the boys and $10\%$ of the girls offer Mathematics. The girls constitute $60\%$ of the total number of students. If a student is selected at random and is found to be studying Mathematics,the probability that the student is a girl,is

There are $n$ different objects $1, 2, 3, \dots, n$ distributed at random in $n$ places marked $1, 2, 3, \dots, n$. The probability that at least three of the objects occupy places corresponding to their number is

Three dice are thrown simultaneously. What is the probability of obtaining a total of $17$ or $18$?

Three mangoes and three apples are in a box. If two fruits are chosen at random,the probability that one is a mango and the other is an apple is

Two dice are thrown. Find the probability that the sum is at least $10$ ?