Big Near Doubles: 5+6 Through 9+10

Now for the bigger near doubles! 5+6: double 5 is 10, plus 1 is 11. 6+7: double 6 is 12, plus 1 is 13. 7+8: double 7 is 14, plus 1 is 15. 8+9: double 8 is 16, plus 1 is 17. 9+10: double 9 is 18, plus 1 is 19. The strategy works exactly the same way with bigger numbers!