Question

Two heavenly bodies are respectively $8.9\times {10}^8$ miles and $2.7\times {10}^7$ miles distant from the earth. Approximately how much farther way from the earth is the first than the second?

• A. $6.2\times {10}^7$
• B. $8.6\times {10}^7$
• C. $8.6\times {10}^8$
• D. $86\times {10}^6$
• E. $62\times {10}^8$

Answer 1

The correct option is C $8.6\times {10}^8$

• The required distance is $8.9\times {10}^8-2.7\times {10}^7=(8.9-0.27)\times {10}^8=8.6\times {10}^8$