Question

The difference between the digits of a two digit number is 1. The number itself is more than 5 times the sum of the digits. If the unit digit is greater than the tens digit, find the number.

I need the workings please

Answer 1

xy is the number (doesn't mean x times y)
y-x=1

10x+y>5(x+y)
x<y
y-x=1
y=x+1

10x+y>5(x+y)
10x+y>5x+5y
minus (5x+y) from both sides
5x>4y
sub x+1 for y
5x>4(x+1)
5x>4x+4
minus 4x
x>4
y=x+1
y>5
the number can be
56,67,78,89