Which of the following n umbers will replace the question mark (?) in the given series?
 78, 112, 64, ?, 50, 140 

Which of the following numbers will replace the question mark (?) in the given series?
 19, 38, 35, ?, 135, 810

Which letter cluster will replace the question mark (?) to complete the given series?
 WFBI, UCWB, SZRU, ?

Which of the f ollowing numbers will replace the question mark (?) in the given series?
 15, 27, 12, ?, 9, 33

Which of the follow ing numbers will replace the question mark (?) in the given series
 13, 14, 23, 48, 97, 178, ? 

Which of the following numbers will replace the question mark (?) in the given series
 13, 14, 23, 48, 97, 178, ? 

Select the letter-pair that can replace the question mark (?) in the following series.

AR, CU, EX, GA, ?

Select the letter-cluster from among the given options that can replace the question mark (?) in the following series.
AAI, AEI, AII, AOI, ?