If you have two terms in a sequence, then a term decreased by the previous term=common difference
so
30 and 27
27 decreased by 30 is -3
the common differce is -3
Step-by-step explanation:

Found this on socratic !!! hope this helps !!!!
Answer:
12/5 or 2 2/5
Step-by-step explanation:
3/5+3/5+3/5+3/5
=> (3+3+3+3) / 5
=> 12/5
=> 2 2/5
Hope it helps......