Question

One of the digits of a two digit number is five times the other.if we interchange the digits of this number and add the resulting number to the original number ,we get 66. What is the original number.

Answer 1

Answer:

51

Step-by-step explanation:

let the number be ab=(10*a)+(1*b)

a=5b

10*a+1*b+10*b+1*a=66

10(a+b)+(a+b)=66

(a+b)(10+1)=66

a+b=6

5b+b=6

b=1

a=5

Answer 2

Answer:

51 or 15

Step-by-step explanation:

Let the units digit be x

Let the tens digit be 5x

Number formed= 10(5x)+x

=50x+x

=51 x

Number formed after reversing=10x+5x

=15x

Hence, 15x+51x=66

=66x=66

x=66/66

x=1

51x=51*1

=51

15x=15*1

=15

Since they have not mentioned whether the units or tens digit is five times the other, the original number is 51 or 15