A glacier advances toward the sea 0.04 miles annually. In 2010 the front of the glacier is 6.9miles from the mouth of the sea. How far will it be from the sea in 2030?

Answer: 6.1 miles

Step-by-step explanation:

Here, In 2010 the front of the glacier is 6.9 miles from the mouth of the sea.

And, it advances toward the sea 0.04 miles annually.

Thus, till 2030 it will advance toward the sea = 20 * 0.04 = 0.8 miles

Therefore, Its distance from the sea in 2030 = 6.9 - 0.8 = 6.1 miles

⇒ it will be 6.1 miles far from the sea in 2030