Question

3. Jocelyn needs to study two stars for her astronomy research. She has narrowed her choices down to four stars that are located on a straight line from earth. Star Distance from earth Star A 0.176 times 10 to the power of 18 km Star B 22.13 times 10 to the power of 16 km Star C 31.42 times 10 to the power of 14 km Star D 125.5 times 10 to the power of 15 km Jocelyn wants to study the two stars that are closest to each other. (a) Which two stars should she study? (b) What is the distance between the two stars? Show or explain your work.

Answer 1

A 0.176 times 10 to the power of 18 km =
A 176.0 times 10^15 km

B 22.13 times 10 to the power of 16 km =
2.213 x 10^15 km

C 31.42 times 10 to the power of 14 km =
3.142 x 10^15 km

D 125.5 times 10 to the power of 15 km

The recalculated list is now:
A 176.0 times 10^15 km

B 2.213 x 10^15 km

C 3.142 x 10^15 km

D 125.5 x 10^15 km

Just by looking, we can see the 2 stars closest to each other are
C 3.142 x 10^15 km and
B 2.213 x 10^15 km

The distance between them = 3.142 x 10^15 km -2.213 x 10^15 km
.929 x 10^15 km =
9.29 x 10^14 km