Simple Equations:

1. The product of two consecutive odd numbers is 4623. Which is the greater of the two numbers?

A. 66                      B. 69                      C. 68                      D. 67                      E. None of these

Ans. B

Solution:

 X (X + 2) = 4623

X² + 2X – 4623 = 0

X² + 69X – 67X – 4623 = 0

(X - 67)(X + 69) = 0

X = 67, Greater odd number = X + 2 => 67 + 2 = 69

2. If the numerator of a fraction is increased by 500% and the denominator is increased by 300%, the resultant fraction is 1(1/17). What was the original fraction?

A. 12/17               B. 13/17                C. 3/7                    D. 4/11                  E. None of these

Ans. A

Solution: (X + 5X)/(Y + 3Y) = 18/17

= >            X/Y = 12/17

3. The number obtained by interchanging the digits of a two-digit number is less than the original number by 63. If the sum of the digits of the number is 11, what is the original number?

A. 29                      B. 92                      C. 74                      D. Cannot be determined           

Ans. B

Solution: 10X + Y – (10Y + X) = 63

 9X – 9Y = 63

X – Y = 7

X + Y = 11

Solving these equations, we get

X = 9, Y = 2

Required number = 10X + Y

=> 10 * 9 + 2 = 92

4. In how many different ways can the letters of the word DAILY be arranged?

A. 60                      B. 498                    C. 160                    D. 120

Ans. D

Solution: Number of different ways in which the letters of the word DAILY be arranged = 5!

=>  5 * 4 * 3 * 2 * 1 = 120

5. By how much is 3/5 of 735 greater than 2/3 of 633?

A. 17                      B. 13                      C. 23                      D. 20                      E. None of these

Ans. E (19)