Number System If A + B = 30 and AB = 94, What is the value of A² + B² ? 920 712 824 625 920 712 824 625 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 The sum of the squares of three numbers is 138, while the sum of their products taken two at a time is 131. Their sum is: 20 None of these 30 40 20 None of these 30 40 ANSWER DOWNLOAD EXAMIANS APP
Number System If (83)² is subtracted from the square of a number, the answer so obtained is 8487. What is the number ? 146 124 179 163 146 124 179 163 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the number be x Therefore, x² - (83)² = 8487x² = 8487 + (83)²x² = 8487 + 6889x² = 15376Therefore, x² = 15376 x = 124
Number System On dividing number by 5, we get 3 as remainder. What will be the remainder when the square of this number is divided by 5? 2 4 0 1 2 4 0 1 ANSWER DOWNLOAD EXAMIANS APP
Number System How many numbers up to 100 and 300 are divisible by 11? 22 20 18 21 22 20 18 21 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP (300 – 100)/11 = 200/11 = 18 2/1118 Numbers
Number System If a + b = 16 and ab = 68, what is the value of a² + b² ? 112 116 120 124 112 116 120 124 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP a + b = 16 Therefore, (a+b)² = (16)² = 256 a² + b² + 2ab = 256Therefore, a² + b² = 256 - 2 x 68Therefore, a² + b² = 256 - 136 = 120
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