Question

In astronomy, the immense distances between celestial bodies are measured in light– years; the distance that light can travel in one year. One light– year is approximately 6,220,000,000,000 miles. If a star is 7.2 light– years from Earth, which expression in correct scientific notation represents the number of miles the star is from Earth? Round to the tenth.

Answer 1

The distance to a star that is 7.2 light-years from Earth, in miles and in scientific notation, is 4.5 × 10±´ miles.

Step-by-step explanation:

To express the distance of a star that is 7.2 light-years away from Earth in miles using scientific notation, we first need to know that one light-year is approximately 6,220,000,000,000 miles, or 6.22 × 10±² miles. Multiplying this by the distance in light-years gives us the distance in miles: 7.2 light-years × 6.22 × 10±² miles/light-year = 44.784 × 10±² miles. When rounded to the tenth in scientific notation, this becomes 4.5 × 10±´ miles.