Data Sufficiency

A phone company charges 3/4 of its regular per-minute rate for
long-distance calls for each minute in excess of 1000 per
month, excluding calls made on Sundays, and 1/2 of its regular per-minute rate for all long-distance calls made on Sundays. How much did the phone company charge Victoria last month?

(A) Last month, Victoria made a total of 1500 minutes worth of long-distance calls, including 200 minutes worth on Sundays.

(B) The regular rate for long-distance calls is $0.10 per minute.

Should be C.

Total cost = 1000 * 0.10 + (300 * 0.75 * 0.10) + (200 * 0.5 * 0.10)

But we don't know whether he called all the sunday 200 mins within the first 1000 mins or after 1000 mins. right?

You may have misread the question. The phone company charges 1/2 it's normal charge for Sunday calls, regardless of whether the caller has made any other calls. So if I make 200 minutes of calls on Sunday only and no other calls during weekdays, my bill will be $10 for the month. the 1000 minute threshold only applies to calls made Monday thru Saturday.

tngearhart,
thanks for pointing out. I misunderstood the question.