Question

the sum of the digits of a two digit number is 12 . if the digits are reserved the new number becomes 4 upon 7 time the original number . find the original number​

Answer 1

Answer:

Let the two digit number be 10x+y

Sum of digit : x+y=12 __(i)

A.t.Q : 2(10x+y)−(10y+x)=12

⇒20x+2y−10y−x=12

⇒19x−8y=12

⇒19x−8y−12=0 __(ii)

Put eq. (i) in eq. (ii)

⇒19(12−y)−8y−12=0

⇒228−19y−8y−12=0

⇒27y=216

⇒y=8

x+y=12

x=12−8

x=4

Number : 48