Aptitude - Number System Online Quiz
Following quiz provides Multiple Choice Questions (MCQs) related to Number System. You will have to read all the given answers and click over the correct answer. If you are not sure about the answer then you can check the answer using Show Answer button. You can use Next Quiz button to check new set of questions in the quiz.
Answer : D
Explanation
Unit Digit in (384)1793 = Unit Digit in (4)1793 = Unit Digit in (42)896 x 4 = Unit Digit in (6 x 4) = 4 Unit Digit in (1035)317 = Unit Digit in (5)317 = 5 Unit Digit in (261)491 = Unit Digit in (1)491 = 1 Therefore, unit digit in (384)1793 x (1035)317 x (261)491 = Unit Digit in (4 x 5 x 1) = 0
Q 2 - Which of the following numbers is completely divisible by 45?
Answer : C
Explanation
45 = 5 x 9
So, co-primes are 5 and 9
For divisibility, the unit digits must be 0 or 5 and sum of digits must be divisible by 9.
The unit digit of 2025 is 5 and sum of digits is divisible by 9
Therefore, 2025 is completely divisible by 45.
Q 3 - The sum of the two numbers is 12 and their product is 35. What is the sum of the reciprocals of these numbers?
Answer : A
Explanation
Let numbers be p and q.
p + q = 12 and pq = 35
(p + q)⁄pq = 12⁄35
1⁄q + 1⁄p = 12⁄35
Answer : C
Explanation
7, 14, 21, ..., 98
A.P: a = 7, d = 7, l =98
tn = 98
= a + (n - 1)d
i.e. 98 = 7 + (n - 1)7
n = 14
Sum = n⁄2 (a + l)
= 14⁄2 (7 + 98 )
= 735
Q 5 - A number when divided by 296 leaves 75 as remainder. When the same number is divided by 37, the remainder will be?
Answer : C
Explanation
Lets x = 296q + 75 = (37 + 8q + 37 x 2) + 1
= 37 + (8q + 2) + 1
When the number is divided by 37, the remainder is 1.
Answer : C
Explanation
As (a+b) always divides (an - bn) if n is an even number. ∴ 17200 - 1200 is divisible by 17 + 1 ∴ 17200 - 1 is divisible by 18 ∴ When 17200 is divided by 18, remainder is 1.
Answer : A
Explanation
916 x y x 3 = 214344 => 2748 x y = 214344 => y = 214344 / 2748 => y = 78
Answer : A
Explanation
y = 12846 x 593 + 12846 x 407 = 12846 x (593 + 407) = 12846 x 1000 = 12846000
Answer : D
Explanation
91. As it is divisible by 7.
Answer : C
Explanation
Using formulae (a-b)2 = a2 + b2 - 2ab ab = (a2 + b2 - (a-b)2) / 2 => ab = [41 - (5)2] / 2 = 8
