Question

A light-year is a unit used to measure large distances in space. One light-year is approximately equal to 5.88 trillion miles. On a map of the Milky Way Galaxy, the scale is 1 inch:70 light-years. If two stars on the map are 19 inches apart, about how far apart are they in the galaxy?

Answer 1

Answer:

$7.8204\times 10^{15}\ \text{miles}$

Step-by-step explanation:

In the map the scale is

$1\ \text{inch}=70\ \text{light-years}$

So

$19\ \text{inches}=19\times 70=1330\ \text{light-years}$

In miles

$1\ \text{light-year}=5.88\times 10^{12}\ \text{mi}$

$1330\ \text{light-years}=1330\times 5.88\times 10^{12}=7.8204\times 10^{15}\ \text{miles}$

The galaxies are $7.8204\times 10^{15}\ \text{miles}$ apart.