IBM Company Numerical Ability Probability

A number is selected at random from first thirty natural numbers. What is the chance that it is a multiple of either 3 or 13?

Read Solution (Total 2)

the 1st 30 natural nums are 1...30
inthat multiple of 3 0r 13
then the multiples of 3 or13 are =3,6,9,12,15,18,21,24,27,30 and 13,26=12
probability =12/30=2/5
13 years agoHelpfull: Yes(27) No(1)

Multiple of 3=3,6,9,12,15,18,21,24,27,30
Multiple of 13=3,26
Total of all multiple is 12, therefore the probability is:
12/30=2/5
12 years agoHelpfull: Yes(3) No(0)

IBM Other Question

An anti aircraft gun can fire four shots at a time. If the probabilities of the first, second, third and the last shot hitting the enemy aircraft are 0.7, 0.6, 0.5 and 0.4, what is the probability that four shots aimed at an enemy aircraft will bring the aircraft down? A man can hit a target once in 4 shots. If he fires 4 shots in succession, what is the probability that he will hit his target?