Question

The average distance between the earth and sun is 149000000. This distance can be written as ___________.

• A. $1.49\times {10}^8$
• B. $14.9\times {10}^7$
• C. $0.149\times {10}^9$
• D. $14.9\times {10}^8$

Answer 1

Answer: (A), (B), (C)

The correct options are
A $1.49\times {10}^8$
B $14.9\times {10}^7$
C $0.149\times {10}^9$

Given: distance between the earth and sun is 149000000
Now, put a decimal point at the rightmost position of the number.
$\Rightarrow$ Then number becomes 149000000.
If one wants to write the number as $1.49\times {10}^8$, then move the decimal point eight places to the left and put the decimal point there and take the power as the number of places moved.
If one wants to write the number as $14.9\times {10}^7$, then move the decimal point seven places to the left and put the decimal point there and take the power as the number of places moved.
If one wants to write the number as $0.149\times {10}^9$, then move the decimal nine seven places to the left and put the decimal point there and take the power as the number of places moved.