Question

In a two digit number,digit at the tens place is twice the digit
at units place.if the number obtained by interchangingthe digits is added to the original number,the sum is 66.find the number

Answer 1

Answer:

Let the units digit be x and tens digit be 2x.

Original no.=10*2x+x=21x

no. formed after interchanging digits=10*x+2x=12x

according to the question,

21x+12x=66

33x=66

x=66/33=2

original no.=10*2*2+2=42