B=A+5 10A+B=3(A+B) Replace the B’s in the bottom equation with A+5s, because we know that’s the same thing from the top equation
10A+A+5=3(A+A+5) 11A+5=3(2A+5) 11A+5=6A+15 5A=10 A=2 Then B is 5 more than that so B=7 Your number is 27 **To double check** When we double check this and see 7 is 5 more than then 2. Then 27 is three times what we get when we add the digits (2+7=9).