Fill in the numbers regularly in grade one 3.4.9.9.15.14. (). 19. ()

Fill in the numbers regularly in grade one 3.4.9.9.15.14. (). 19. ()

3+6 4+5
9+6 9+5
15+6=21 14+5=19
21+6=27 19+5=24
Fill in 21 27 24