Question 526424
Let
Bob's house number = x+1
Laura's house number = x+3

Sum of the numbers
x+1+x+3=524
2x+4=524
2x=524-4
2x=520
2x/2=520/2
x=260


Bob's house number = x+1 = 260+1 = 261
Laura's house number = x+3 = 260+3 = 263