Subject: General Aptitude · Chapter: Problems on Numbers · Exam: 2005 · Marks: · Difficulty:
In a three-digit number, the digit in the units place is four times the digit in the hundreds place. If the digits in the units place and the tens place are interchanged, the new number so formed is 18 more than the original number. If the digit in the hundreds place is one-third of the digit in the tens place, what is the original number?
Answer
Answer (as printed):
Explanation
Let the digit in the hundreds place be x. Then, digit in the units place = 4x. And, digit in the tens place = 3x. Original number = 100x + 10 × 3x + 4x = 100x + 30x + 4x = 134x. Number formed on interchanging the unit’s and ten’s digits = 100x + 10 × 4x + 3x = 143x. \ 143x – 134x = 18 ⇔ 9x = 18 ⇔ x = 2. Hence, original number = 134x = (134 × 2) = 268.
Explanation as extracted from the printed page; notation may be imperfect.