Data from two production faces of an open pit iron ore mine are given.
| Item description | Face 1 | Face 2 |
| Maximum production capacity (tonne/day) | 1600 | 2000 |
| Fe (%) | 63 | 58 |
| Production cost of ores (in INR/tonne) | 1500 | 1200 |
Ores from two different faces are blended and supplied with Fe grade not less than 60 %. Based on the demand, the combined production is limited to a maximum of 2500 tonne/day. If the selling price of blended iron ores is INR 4500 /tonne, the optimal production from two faces in tonne/day, for maximizing the profit, respectively are