71. Which of the following Roman numeral is meaningless?
(A) XCIV
(B) CCCXLIX
(C) LXIIII
(D) CXLII
Answer:
(C) LXIIII
Explanation:
The rules of Roman numerals state that a symbol cannot be repeated more than three times consecutively. The number 4 is represented by “IV”, making the “IIII” in LXIIII an invalid and meaningless string.
72. Predecessor of the smallest 6 digit number:
(A) 99999
(B) 10000
(C) 999999
(D) 100000
Answer:
(A) 99999
Explanation:
The smallest 6-digit number is 100,000. Its predecessor is the number exactly one less, which is (the largest 5-digit number).
73. Which pair is not a twin prime?
(A) (3, 5)
(B) (11, 13)
(C) (13, 15)
(D) (17, 19)
Answer:
(C) (13, 15)
Explanation:
Twin primes are pairs of prime numbers that differ by exactly 2. While 13 is prime, 15 is a composite number (divisible by 3 and 5), meaning the pair (13, 15) cannot be twin primes.
74. Reciprocal of 6(2/5)
(A) 32/5
(B) 30/6
(C) 5/32
(D) 6/32
Answer:
(C) 5/32
Explanation:
First, convert the mixed number to an improper fraction: . The reciprocal is found by flipping the numerator and denominator, resulting in .
75. A square has perimeter 100 cm. Its area is:
(A) 200 Sq cm.
(B) 400 Sq cm.
(C) 526 Sq cm.
(D) 625 Sq cm.
Answer:
(D) 625 Sq cm.
Explanation:
A square has 4 equal sides. If the perimeter is 100 cm, one side is cm. The area is , so Sq cm.
