Answer:
See below
Explanation:
From 5 to 10 mugs is 5 mugs
These cost 110 - 67.50 = 42.50
So each mug costs 42.50 / 5 = 8.50 each
With a 'base cost' of 25 dollars
(Base cost might be artwork, design, order processing, shipping or whatever.....but this amount is added to each order)
(As a check 20 mugs would be 25 + 20 (8.50) = 195 <====yep
150 mugs will then be 25 + 150 ( 8.50) = 1300 dollars