During a one day sale, a store sold each sweater of a certain type for $30 more than the store's cost to purchase each sweater. how many of those sweaters were sold during the sale?
1) During the sale the total revenue from sale of these sweaters was $270
2) During the sale, the store sold each of these sweaters at a price that was 50% greater than the store's cost to purchase each sweater.
Sale price = $30 + Cost price, or
S = $30 + C
1) Insufficient. Each sweater could have been sold for 60 or 230.
If n sweaters were sold, we have n*S = 270
2) Insufficient. 50% greater = $30, hence
or S = 1.5*C
Plugging this in the first equation, we get S = 90, C = 60. But we still don't have n.
Combining (1) & (2): n*90 = 270
or n = 3
My GMAT debrief