Question

a number consisting of two digits is 7 times the sum of digit when 27 is subtracted from the number the digits are reserved find the number

Answer 1

Hey

Here is your answer,

Let the unit place digit be x .

and tens place digit be y.

then,the no. formed = 10y+x

=(10y+x)= 7(x+y)
= 10y+x= 7x+7y
= 3y-6x= 0
= 3y= 6x
= y= 2x.........(i)

No. formed after reversed= 10x+y
10y+x-27= 10x+y
9y-9x= 27
y-x= 3

putting value of x from equation (i) in (ii)
2x-x= 3
x= 3

so ,y= 6

hence ,the no. obtained = 63.

Hope it helps you!