J.K. Chopra Solutions for Chapter: Reasoning (lncluding Mathematical), Exercise 37: Practice Exercise

There are two men aged $26$ and $30$years. The probability to live $35$years more is$0.67$ for $26$years old man and $0.60$ for $30$ year old man. The probability that at least one of these men will be alive $35$years hence is:

A bag contains $7$red and$5$ white balls. Two successive draws of $2$balls are made without replacement. The probability that the in the first draw $2$ white balls and in the second draw $2$ red balls be chosen is:

A speaks truth in $65\%$ of the cases and $\mathrm{B}$ in $80$of the cases. In what percentage of cases are they likely to contradict each other in stating the same fact?

In a certain school, $20\%$ students failed in English, $15\%$ students failed in Mathematics and $10\%$ students failed in both English and Mathematics. A student is selected at random. If he failed in English, what is the probability that he also failed in Mathematics?

The probabilities that on a certain day the two trains from Chennai and Ahmedabad arrive on time at Mumbai are $0.93$ and$0.89$. The probability that both the trains arrive at time is $0.87$. The probability that at least one train is on time is:

A can hit a target $4$times in $5$ shots, B hits$3$times in $4$shots and C hits twice in $3$shots. They fire together. The probability that at least two shots hit the target is:

Probability of occurence of two events A and B are $0.25$ and $0.50$. Probability of simultaneous occurence of A and B are $0.14$. The probability that neither A nor B occur is:

A bag contains $4$ red and$7$ green balls and another bag contains $8$ red and$5$green balls. One ball is transferred from first bag to the second bag without noticing its colour. A ball is then drawn from the second bag. The probability that it is a green ball is: