# Aptitude Questions : Number System Set 9

Hello Aspirants. Welcome to Online Quantitative Aptitude Section with explanation in AffairsCloud.com. Here we are creating question sample in Number System, which is common for all the competitive exams. We have included Some questions that are repeatedly asked in bank exams !!

Questions Penned by Yogit

1. The sum of the digits of two-digit number is 5. If the number is reversed, the number is decreased by 27. Find the number?
a) 14
b) 41
c) 31
d) 31
e) None of these
Explanation :
Let the number be (10a + b)
given, a +b = 5 and (10a + b) – (10b +a) = 27
a – b = 3 and a +b = 5

2. The ratio between a two-digit number and the sum of the digits of that number is 3:1. If the digit in the unit’s place is 5 more than digit at ten’s place, what is the number?
a) 17
b) 27
c) 36
d) 34
e) None of these
Explanation :
Let the two-digit number be 10a + b
(10a + b)/(a+b) = 3/1, 7a = 2b
And also given b = 5 + a
Solve both equations to get the number

3. How many numbers are there up to 1000 which are divisible by 4, 6 and 8 together?
a) 39
b) 40
c) 41
d) 42
e) None of these
Explanation :
LCM of 4,6 and 8 is 24
Divide 1000 by 24, we get quotient  = 41 and 16 as remainder
so 41 numbers are there which are divisible by 4,6 and 8 together.

4. What is the number in the unit place of the number (129)^58?
a) 1
b) 2
c) 4
d) 9
e) None of these
Explanation :
[(129)^2]^29 = (1)^29 = 1 (9^2 always result in 1 on unit place)

5. A number when divided by 5 leaves a remainder 4. What is the remainder when the square of the same number is divided by 5?
a) 1
b) 2
c) 4
d) 3
e) None of these
Explanation :
Le the number be 5a + 4
square of the number = 25a^2 + 16 + 40a
so remainder = 1 (16 divided by 5 leaves a remainder 1)

6. When a number is divided by 527 gives the remainder as 21. When the same number is divided by 17, the remainder will be?
a) 2
b) 3
c) 4
d) 7
e) None of these
Explanation :
Let the number be 527a + 21
when divided by 17, 527a is divisible by 17 and leaves remainder as 4 when 21 is divided by 17

7. If 4 is added to the numerator of a fraction it becomes 1/3 and if 3 is added to the denominator it becomes 1/6 then find the difference between numerator and denominator is
a) 20
b) 21
c) 22
d) 24
e) None of these
Explanation :
(a +4)/b = 1/3 and a/(b+3) = 1/6 solve both the equations, u will get a = 5 and b = 27

8. When one-fourth of a number is added to 16, it becomes three-fourth of itself. Find the number?
a) 24
b) 32
c) 36
d) 48
e) None of these
Explanation :
a/4 + 16 = 3a/4,
2a/4 = 16, so a = 32

9. In the examination a candidate must get 3/8th marks to pass, out of total marks. Shyam appeared in the exam and got 300 marks and still failed by 36 marks. The maximum mark is
a) 856
b) 866
c) 876
d) 886
e) 896
Explanation :
Let total marks = M
(3/8)*M = 300 + 36 = 336
M = 112*8 = 896

10. Two different numbers are divided by the same divisor and left remainder 11 and 17 respectively and when their sum was divided by the same divisor, remainder was 4. What is the divisor?
a) 20
b) 24
c) 25
c) 26
d) 28
e) None of these