Respuesta :

C. 31 sit-ups/day -

The way you would get this answer is by dividing 279 by 9; 279/9 = 31.

Hope this helps!

Answer: C 31 sit-ups/day

Step-by-step explanation: This is because if you divide 279/9 it would give you how many situps you did in total of those 9 days each.

RELAXING NOICE
Relax