Number System If x + y = 61 and xy = 888, What is the value of x²+ y² ? 1975 1955 1945 1965 1975 1955 1945 1965 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Because (x + y)² = x² + y² + 2xy∴ x² + y² = (x + y)² - 2xy∴ x² + y² = (61)² - 2 x 888= 3721 - 1776 = 1945
Number System If the sum and difference of two numbers are 20 and 8 respectively, then the difference of their square is: 28 180 12 160 28 180 12 160 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the numbers be x and y. Then, x + y = 20 and x - y = 8x2 - y2 = (x + y)(x - y) = 20 * 8 = 160.
Number System Look at this series: 1000, 200, 40, ... What number should come next? 8 24 14 2 8 24 14 2 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP This is a simple division series. Each number is divided by 5. Rule = (1st number / 5 = 2nd number) (2nd number / 5 = 3rd number)....Now, (1000 / 5 = 200), (200 / 5 = 40), (40 / 5 = 8)...So answer is a = 8.
Number System 7.8% of 12.5 + 2.5% of 161 = ? 12 2 9 5 12 2 9 5 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 7.8 x 12.5/100 + 2.5 x 161/100= 0.975 + 4.025= 5
Number System 50% of 8/15 of 9/4 of 5/3 of 333 = ? 666 333 444 555 666 333 444 555 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 50% of [8x9x5/15x4x3 x 333]= 50% of 666= 333
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