Question : By interchanging the digits of a two-digit number, we get a number that is four times the original number minus 24. If the unit's digit of the original number exceeds its ten's digit by 7, then the original number is:
Option 1: 29
Option 2: 36
Option 3: 58
Option 4: 18
Latest: SSC CGL preparation tips to crack the exam
Don't Miss: SSC CGL complete guide
Correct Answer: 29
Solution :
Let the original number be (10P + Q) and its reversed number be (10Q + P).
By interchanging the digits of a two-digit number, we get a number that is four times the original number minus 24.
(10Q + P) = 4 × (10P + Q) – 24
⇒ 39P – 6Q = 24
⇒ 13P – 2Q = 8 .....................(i)
Again, Q – P = 7 ....................(ii)
Solving equation (i) and equation (ii),
We get, P = 2 and Q = 9
The original number is 10P + Q = 10 × 2 + 9 = 29
Hence, the correct answer is 29.
Related Questions
Know More about
Staff Selection Commission Combined Grad ...
Answer Key | Eligibility | Application | Selection Process | Preparation Tips | Result | Admit Card
Get Updates Brochure
Your Staff Selection Commission Combined Graduate Level Exam brochure has been successfully mailed to your registered email id “”.
