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* AC DD chaircar is inferior to normal AC chaircar in comfort, the same way as ACIII is inferior to ACII.
* cost per berth of ACIII coach (72berths/coach) is lesser than the cost per berth of ACII coach (54 berths/ coach), so fare of ACIII (33% extra berths)is 30% lesser than ACII. If cost of bedding is taken into account, the fare difference shall be more than 30%.
* Similarly cost per seat of ACDD coach (120 seats/coach) is lesser than the cost per seat of normal AC coach (78 seats...
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per coach),
* accordingly, the fare of AC DD (54% extra berths) should be about about about 50% lesser than normal ACC fare. Owing to complication in ACDD coach construction, this fare can be kept around 60%.
* Fare of congested ACDD seat from Mumbai to Ahmedabad in ACDD chair car is Rs 664/- against only Rs. 553/- for ACIIIE berth in GR and Rs. 313/- for non ac Sleeper berth.
* Clearly ACDD seats are overpriced and IR is trying to profiteer from it, this is the main reason for failure of most of ACDD trains. Most of people dislike these trains and prefer normal AC chaircar which costs the same but is much more comfortable.