Number System
The population of a town increases by 15% in the first year and decreases by 25% in the second year. If its current population is 168480 then what will be its population after two years ?
Total balls = 4 + 6 + 7 = 17∴ n(S) = 17C1 = 680Two red balls can be selected from four red balls in 4C2 = 6 ways.and the third ball can be selected from the remaining 13 balls in 13C1 = 13 ways.∴ P (E) = 13x6/680 = 39/340
EXAMIANS