TNPSC Maths question paper with answers
1.
The counting number 1,2, 3, are called.
a)
Whole numbers
b)
Natural numbers
c)
Integers
d) None.
Natural numbers
2.
The other name for the whole number?
a)
negative integers
b)
integers
c)
natural no's
d)
non-negative integers.
non-negative integers.
3.
The G.G.D of two prime numbers is
a)
1
b)
Prime number
c)
composite no
d)
o
1
4.
The smallest two digit prime number is
a)
37 b) 7 c) 11 d) 10
[largest
2-digit prime à 97. Smallest 3-digit prime à
101]
11
5. The least value of x for which 72X5462 is exactly divisible by 9 is
(a) 6 (b) 3 (c) 9 (d) 7
Solution
For divisible by 9, we get multiple of 9
While adding the digits.
So, 7+ x + 5 + 4 + 6 + 2 = multiple of 9
24+2 = multiple of 9 = 27 (or) 2+4+2
24 + = 27 6+x=9
Ans: 3 X=3
3
6.. A number having non-terminating and (சுடில் தண்மை) recurring decimal
expression is
a) an integer
b) a irrational no.
c) an rational number
d) a whole number.
a irrational no.
7. If a number has a non-terminating and non-recurring decimal expansion
then it is
a) a rational number.
b) a natural number
c) an irrational number
d) integer.
an irrational number
8. Which the Following is not true?
a) Every natural no is a rational no.
b) Every real no is a rational no.
c) Every whole no is a rational no.
d) Every integer no is a rational no.
Every real no is a rational no.
9. In a set of First x natural no's there are 30 prime numbers. Find the
number of composite numbers in the above get.
a) x-20 b) 30-x c) x-29 d) x-31
ANS D
x-31
10. Which of the following is / are true ?
1. All divisor of a no. are also factor for that no
2. All Factors of a no are also divisors for that no.
3. All divisors of a. no need not be factors
4. All Factors of a no need not be divisors for that no.
a) 2, 3
b) 1, 2
c) 1, 2, 3
d) all the four
All divisor of a no. are also factor for that no
11. Find the smallest number, having Four different prime factors
a) 210
b) 330
C)147
d) 30
Solution: 30 = 5 x 2 x 3
147 = 7 x 7 x 3
210 = 5 x 2 x 7 x
3 à 210 is smallest
320 = 5 x 2 x 3 x
11
210
12. If the number 48387x8 is divisible by 11, find the missing number
a) 1
b) 2
c) 3
d) 4
solution
(4+3+7 +8) - (8 + 2 + x) = 0 or (1
22-10-x= 0 or l1
12-x = 0 or 11.
x=1
1
13. If n,n+2, n+4 are prime no's, the least value of n is
a) 7
b) 2
c) 3
d) 1
solution:
n=7 7,9,11
n = 2 2,4,6
n = 3 3,5,7
n = 1 1,3,5
1
14. when 385 is added to 5A7, the result is 8B2 is divisible by 3. What
is the largest possible value of A?
a) 8 b) 2 c) 1 d)
4
4
15. Which one of the following is the pair of twin primes?
A) 7,9
B) 19, 21
C) 29, 31
D) 47, 49.
29, 31
