Proportions or Ratios are 2 fractions that are equal?

Proportion.

Step-by-step explanation:

A proportion can normally be written as two equivalent fractions.

Option A

Distance of each boat from light house is approximately 20 miles.

Solution:

The diagram of this question is attached below

In the attached figure A and B represents position of two boats and C represents position of light house.

Given that CA = CB and  

So triangle ABC is isosceles triangle with angle

 [Angle opposite to equal side CA and CB]

[Angle sum property of triangle]

Construct a median CE on AB,

AE = EB  [ Since CE is median]

In triangle AEC,

Hence AC that is distance of each boat from light house is approximately 20 miles.