Complete the given series in both directions.
____ ____ 150, 200 ___ ___ 350 ___

The correct answer is: 50, 100, 250, 300, 400

Step by step solution:
150 + 50 = 200
So, the series might be numbers that have a difference of 50 kin an increasing order.
____ ____ 150, 200 ___ ___ 350 ___
We have got two blanks before 150, so the first term will be 150 - 100 = 50
second term, 50 + 50 = 100
third term, 100 + 50 = 150 (given)
fourth term, 150 + 50 = 200 (given)
fifth term, 200 + 50 = 250
sixth term 250 + 50 = 300
seventh term,  300 + 50 = 350
eighth term, 350 + 50 = 400
Thus, the series is 50, 100, 150, 200, 250, 300, 350, 400
Thus, the missing terms are 50, 100, 250, 300, 400.
Hence, option(a) is the correct option.