Problema Solution
the ten's digit of a two-digit number is 3 more than the unit's digit. find the number if it is 7 times the sum of its digits.
Answer provided by our tutors
Let the no be 10x+y
So x-y=3
or x=3+y
Again 10x+y= 7 (x+y)
or 10x+y= 7x+7y
or 3x=6y
or x=2y
or 3+y=2y
or y=3
So x= 3+y=6
So the number is 10x+y =10*6+3=60+3=63