By using dot (.) patterns, which of the following numbers can be arranged in all the three ways namely a line, a triangle and a rectangle?
(A) 9 (B) 10 (C) 11 (D) 12
Which of the following is not true?
(A) (7 + 8) + 9 = 7 + (8 + 9)
(B) (7 × 8) × 9 = 7 × (8 × 9)
(C) 7 + 8 × 9 = (7 + 8) × (7 + 9)
(D) 7 × (8 + 9) = (7 × 8) + (7 × 9)
A whole number is added to 25 and the same number is subtracted from 25. The sum of the resulting numbers is
(A) 0 (B) 25 (C) 50 (D) 75
The product of a non-zero whole number and its successor is always
(A) an even number (B) an odd number
(C) a prime number (D) divisible by 3
The product of successor and predecessor of 999 is
(A) 999000 (B) 998000 (C) 989000 (D) 1998
The smallest 4-digit number having three different digits is
(A) 1102 (B) 1012 (C) 1020 (D) 1002
The largest 5-digit number having three different digits is
(A) 98978 (B) 99897 (C) 99987 (D) 98799
Which of the following numbers in Roman numerals is incorrect?
(A) LXXX (B) LXX (C) LX (D) LLX