Ask HN: If earth was the size of a coin, how far to the nearest star?
An 8 year old asked me....
Googling "earth size": Earth radius: 6371 km
Googling "distance to sun in km" Distance to Sun: 149.6 million km
38.1e-4 / x = 6371e4 / 149.6e10
Doing the calculation is left as an exercise to the reader.