Final answer:
The GNP five years ago was approximately $76.0732 billion.
Step-by-step explanation:
To find the GNP five years ago, we can use the formula for exponential growth. Let's assume the GNP five years ago was X billion dollars. We know that it has increased by 63%, so we can write the equation as:
X + 0.63X = 124
Simplifying, we get 1.63X = 124. Solving for X, we divide both sides by 1.63: X = 124 / 1.63 = 76.0732.
Therefore, the GNP five years ago was approximately $76.0732 billion.