Answer:

a 12

Step-by-step explanation:

Answer:

A. 12

Step-by-step explanation:

given sequence : 6,11,9,14,_,17

lets say these as terms(t)

t1=6, t2=11, t3=9, t4=14, t5=?, t6=17, t7=?

t2-t1=11–6=5 ,, t2-t3=11–9=2

t4-t3=14–9=5 ,,

so, difference between t4 and t5 should be 2

t4-t5=2

14-t5=2

t5=14–2

t5=12

now, t6-t5=17–12=5