Answer :
Answer:
T6=23
Step-by-step explanation:
we know that
S6-S5=T6
so 78-55=23= T6
so T6=23
OR
Sñ=n/2(2a+(n-1)d)
given S6=78
6/2(2a+5d)=78
2a+5d=26 :eq1
similarly
S5=5/2(2a+4d)=55
2a+4d=22:eq2
subtract 1 and 2 EQ
d=4
by puting value of d in any eq we get
a=3
now T6=a+(n-1)d
T6=23