Answer:
$4,470,000
Step-by-step explanation:
Cost per ton = Cost - Salvage value / Estimated tons
Cost per ton = 31,420,000 - 3,000,000 / 290,000
Cost per ton = $98 per tons
Tons remaining = 290,000 - 275,000
Tons remaining = 15,000 tons
Book value of the mine at year-end = 15,000 tons*$98 + $3,000,000
Book value of the mine at year-end = $1,470,000 + $3,000,000
Book value of the mine at year-end = $4,470,000