Number System 384×12×2=? 7487 8465 6123 9216 7487 8465 6123 9216 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 9216
Number System The difference between a positive proper fraction and its reciprocal is 9/20. The fraction is: 4/5 3/10 3/5 5/4 4/5 3/10 3/5 5/4 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 1/x - x = 9/20 20x2 + 9x - 20 = 0 20x2 + 25x - 16x - 20 = 0 5x(4x + 5) -4(4x + 5) = 0(4x + 5)(5x - 4) = 0x = 4/5
Number System In how many different ways can the letters of the word "MOBILIZE" be arranged ? 20160 18456 19765 17453 20160 18456 19765 17453 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP The word MOBILIZE has eight letters in which I comes twice ∴ Number of arrangements = 8!/2! = 20160
Number System If A + B = 30 and AB = 94, What is the value of A² + B² ? 920 625 712 824 920 625 712 824 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP (A + B)² = (30)² = 900A² + B² + 2AB = 900Therefore, A² + B² = 900 - 2 x 94 = 900 - 188 = 712
Number System What should come in place of the question mark (?) in the following number series ? 888 888 444 148 ? 7.4 33 35 37 29 33 35 37 29 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 888 ÷ 1 = 888888 ÷ 2 = 444444 ÷ 3 = 148148 ÷ 4 = 3737 ÷ 5 = 7.4
Number System A bag contains four red, six black and seven green balls. Three balls are drawn randomly. What is the probability that the balls drawn contain exactly two red balls ? 45/340 39/340 58/340 51/340 45/340 39/340 58/340 51/340 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 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