A series is given with one term missing. Choose the correct option from the given ones that will complete the series.

50 : 70 ::..?.... 90

2, 10, 30, 68, ?

Select the term that will complete the following letter series.
QN, RP, TS, WW, ___ FH

A series is given with one term missing. Select the correct alternative from the given ones that will complete the series.

RS, ZA, HI, ?

A series is given with one term missing. Select the correct alternative from the given ones that will complete the series.

PON, LKJ, GFE, ?

A series is given with one term missing. Choose the correct alternative from the given ones that will complete the series.

? , Hexane, Heptane, Octane

A series is given with one term missing. Choose the correct option from the given ones that will complete the series.

2 : 7 : 4 : 9 : ?

Select the option that will fill in the blank and complete the given series.
CDZ, DGE, EJJ, FMO, GPT___