Railways
R.R.C. (Kolkata) Solved Paper Held on 17-11-2013
question_answer
A boy was asked to multiply a number by 12. By mistake he multiplied the number by 21 and go this answer 63 more than the correct answer. The number was?
A)7
B)8
C)9
D) 12
Correct Answer:
A
Solution :
As per question? Let the number is x, then \[x\times 21-x\times 12=63\] \[\Rightarrow \]\[9x=63\] \[x=7\]