Question

Astronomers measure large distances in light-years. One light-year is the distance that light can travel in one year, or approximately 5,880,000,000,000 miles. Suppose a star is 13.6 light-years from Earth. In scientific notation, how many miles away is it?

a)5.88 × 1012 miles
b)7.9968 × 1013 miles
c)5.88 × 1013 miles
d)1.36 × 1012 miles

Answer 1

b) 7.9968 × 1013 miles

Explanation:

So one light-year equals 588 × 10^10

13.6 light-years equals 13.6 × 588 × 10^10 = 79968 × 10^9 = 7.9968 × 1013 miles