On one production line in a small custom chip factory, marginal costs decrease rapidly as more chips are made. The marginal cost of making x thousand chips in a day is thought to be C'(x)=40 / the square root of x in hundreds of dollars. Given that it costs 40,000 dollars to make one thousand chips, find the cost of making 16 thousand chips in a day. Total cost in hundreds would be?

2 answers

c'(x) = 40/√x
so, c(x) = 20√x + k
since c(1) = 40,000 = 400*100,
20 + k = 400
k = 380
so, c(x) = 20√x + 380
Now just find c(16)
So when I plug in 16, it gives me 460 but is that meant to be 4,600? I know I can't just put 460 and I know it isn't 460,000. I'm just a bit confused by units.