Number System
The sum of 8 consecutive odd numbers is 656. Also average of four consecutive even numbers is 87. What is the sum of the smallest odd number and second largest even number ?
Average of 8 consecutive odd numbers = 656/8 = 82∴ Fourth number = 82 - 1 = 81∴ First numbers = 75Average of 4 even numbers = 87∴ Second even number = 87 - 1 = 86Second largest even number = 88∴ Required sum = 75 + 88 = 163
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