Assume the cost price of the rocket is CP.
26 % loss => Selling Price = (1-0.26) CP = 0.74 CP
Gained 22 % if the selling price is 144 more => 22 = (0.74 CP + 144 -CP)x100/CP
22 = 74 + 14400/CP - 100
14400/CP = 48
Cost price of the rocket CP = 14400/48
= Rs 300