Number System If the sum of five consecutive even numbers A, B, C, D and E is 130, what is the product of A and E ? 780 660 840 720 780 660 840 720 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the consecutive even numbers be A = 2x, B = 2x + 2, C = 2x + 4, D = 2x + 6 and E = 2x + 8= A + B + C + D + E = 130= 10x + 20 = 130∴ x = 130 - 20/10 = 11Therefore, product of A and E= 22 x 30 = 660
Number System If (47)² is added to the square of a number the answer thus obtained is 2290. What is the number ? 10 7 8 9 10 7 8 9 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the no. be x Therefore, x² + (47)² = 2290Therefore, x² = 2290 - 2209 = 81Therefore, x = 9
Number System Three numbers which are co-prime to one another are such that the product of the first two 551 and that of the last two is 1073. The sum of the three numbers is 93 74 85 110 93 74 85 110 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 85
Number System On multiplying a number by 7, the product is a number each of whose digits is 3. The smallest such number is: 47619 48619 47649 47719 47619 48619 47649 47719 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP By hit and trail, we find that47619 * 7 = 333333.7) 333333 (47619 333333---------------- 0
Number System 450% of a number is 4725. What is 82% of that number ? 871 841 851 861 871 841 851 861 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the number be x.∴ x x 450/100 = 4725= x = 4725 x 100/450 = 1050∴ 82% of 1050 = 1050 x 82/100= 861
Number System If the numerator of a fraction is increased by 200% and the denominator by 300%, the fraction thus obtained is 1/36. What is the original fractions ? 3/9 4/9 5/9 6/9 3/9 4/9 5/9 6/9 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the fractions be x/yx + 200% of x/y + 300% of y = 1/3= x + 2x/y + 3y = 1/3= 3x/4y = 1/3Hence x/y = 4/9