Question

a two digit number is 4 times the sum of its digits the sum of the number formed by receiving its digits and 9 is equal to 2 times the original number find the number​

Answer 1

Answer:

Let the number be 10x+y, where x is the digit at ten's place and y is the digit at ones place.

The number formed in revering the digits is 10y+x.

Given, 10x+y=7(x+y)

⇒10x+y=7x+7y

⇒3x−6y=0

⇒x−2y=0 ....(1)

And 10y+x=6+2(10x+y)

⇒20y+2x=12+10x+y

⇒8x−19y=−12 ....(2)

Solving equations (1) and (2), we get

x=8;y=4

So, the difference of the digits is 8−4=4.