1.) If the number 5 * 2 is divisible by 6, then * =?
A. 2 B. 3
C. 6 D. 7
Answer: Option A Explanation: 6 = 3 x 2. Clearly, 5 * 2 is divisible by 2. Replace * by x. Then, (5 + x + 2) must be divisible by 3. So, x = 2.
2.) The unit digit in the product (784 x 618 x 917 x 463) is:
A. 2 B. 3
C. 4 D. 5
Answer: Option A Explanation: Unit digit in the given product = Unit digit in (4 x 8 x 7 x 3) = (672) = 2
3.) If the number 653 xy is divisible by 90, then (x + y) = ?
A. 2 B. 3
C. 4 D. 6
Answer: Option C Explanation: 90 = 10 x 9 Clearly, 653xy is divisible by 10, so y = 0 Now, 653x0 is divisible by 9. So, (6 + 5 + 3 + x + 0) = (14 + x) is divisible by 9. So, x = 4. Hence, (x + y) = (4 + 0) = 4.
4.) A boy multiplied 987 by a certain number and obtained 559981 as his answer. If in the answer both 98 are wrong and the other digits are correct, then the correct answer would be:
A. 553681 B. 555181
C. 555681 D. 556581
Answer: Option C Explanation: 987 = 3 x 7 x 47 So, the required number must be divisible by each one of 3, 7, 47 ==> 553681 (Sum of digits = 28, not divisible by 3) ==> 553181 (Sum of digits = 25, not divisible by 3) ==> 555681 are divisible by 3, 7, 47.
5.) The Difference between two number s 1365. When the larger number is divided by the smaller one the quotient is 6 and the remainder is 15. The smaller number is?
A. 240 B. 270
C. 295 D. 360
Answer: Option B Explanation: Let the smaller number be x, then larger number = 1365 + x Therefore 1365 + x = 6x + 15 5x = 1350 ==> x = 270 Required Number is 270.
