Question

A jar contains black and white marbles. There are four more black marbles than white marbles. Two marbles are drawn from the jar at random. If the probability that the two marbles are the same color is equal to the probability that the two marbles are different colors, how many marbles are in the bag?

Answer 1

The problem involves combinatorics and algebraic manipulation. $_{r}^{n}\textrm{C}$ is defined as the number of ways of selecting n objects from a set of r objects. The probability of an event is defined as the ratio of the number of ways favourable to the event to the total number of ways. These two ideas were used in solving the problem.

Solving above tuo equations ges Eo 6 : There are io black marbles and 6 white marbles in the jar.