Dorothy Wagner is currently selling 50 "I ♥ Calculus" T-shirts per day, but sales are dropping at a rate of 9 per day. She is currently charging $7 per T-shirt, but to compensate for dwindling sales, she is increasing the unit price by $1 per day. How fast, and in what direction, is her daily revenue currently changing?

Question

anonymous · Answer

I know that it's decreasing, and I got by $18 a day, but apparently I'm wrong

anonymous · Answer

50*7 = 350
41*7 = 287

350-287 =63

increasing the $1
50*8 = 400
42*8 = 336
400-336 = 64