Question 551130
let the number = xy
 two digit number has a value that is eight less than five times the sum of it's digits.
xy=5(x+y)-8
The tens digit is 3 less than the units digit.
x=y-3

take y=4,so x=4-3=1  (if y=3,x=0 so we will not take this combination)
xy=14
check xy=5(x+y)-8
=>14=5(1+4)-8
=>14=25-8
=>14=17 does not satisfies the equation

take y=5,so x=5-3=2  
xy=25
check xy=5(x+y)-8
=>25=5(2+5)-8
=>25=35-8
=>25=27 does not satisfies the equation

take y=6,so x=6-3=6  
xy=36
check xy=5(x+y)-8
=>36=5(3+6)-8
=>36=45-8
=>36=37 does not satisfies the equation

take y=7,so x=7-3=4  
xy=47
check xy=5(x+y)-8
=>47=5(4+7)-8
=>47=55-8
=>47=47 satisfies the equation

so the original number is 47.