Description : 21, 23, 29, 53, 173, _____ a) 210 b) 893 c) 720 d) 253 e) 293
Last Answer : Difference between each successive tam is factorial of number starting from 2, like 23-21 = 2, then 29-23 = 6 means 3!, then 53-29 = 24 means 4!, then next difference is 173-53 = 120 means 5!, so next difference would be 6! i.e. 720 so term will be 173+720 = 893. Answer: b)