Question

The available money in Burger's bank is $\$127$ billion. Select the correct option towards representing $\$127$ billion in a scientific notation.

• A. $\$127\times {10}^9$
• B. $\$12.7\times {10}^{10}$
• C. $\$1.27\times {10}^{11}$
• D. $\$0.127\times {10}^9$

Answer 1

The correct option is C $\$1.27\times {10}^{11}$

Step 1:
Write the given number in exponent form.
$\$127\text{billion}=\$127.0\times {10}^9$

Step 2:
Move the decimal point $2$ places to the left such that it is positioned to the right of the leftmost non-zero digit, $1.$Step 3:
Since the decimal point is moved $2$ places to the left, the exponent to the base $10$ should be a positive integer $2.$

$\therefore \$127\times {10}^9$
$=\$127.0\times {10}^9$
$=1.270\times {10}^2\times {10}^9$
$=1.27\times {10}^2\times {10}^9$
$=1.27\times {10}^{2+9}$ $(\because a^m\times a^n=a^{m+n})$
$=1.27\times {10}^{11}$

Therefore, $\$127$ billion can be written in scientific notation as $\underset{–}{\$1.27\times {10}^{11}}$.

Hence, option (c.) is the correct one.