ABC26GN1669 · Problems on Numbers

Subject: General Aptitude · Chapter: Problems on Numbers · Exam: · Marks: · Difficulty:

Twenty times a positive integer is less than its square by 96. What is the integer?

(a)20

(b)24

(c)30

(d)Cannot be determined

(e)None of these

Answer

Answer (as printed): B

Explanation

Let the integer be x. Then, x2 – 20x = 96 ⇔ x2 – 20x – 96 = 0 ⇔ (x + 4) (x – 24) = 0 ⇔ x = 24.

Explanation as extracted from the printed page; notation may be imperfect.