Question

Find the sum.

$10.1+\frac{1001}{100}+\frac{10001}{1000}+\frac{100001}{10000}$

• A. 40.1111
• B. 1111.1111
• C. 4.1111
• D. 400.1111

Answer 1

The correct option is A

40.1111

When you divide a number by powers of ten (ten times itself some number of times, like ten, one hundred, one thousand, etc.), the decimal moves to the left. ​​For each power of ten, you move one place to the left.

$\frac{1001}{100}=10.01$
[Power of 10 in denominator is 2, so move decimal point 2 places to the left]

$\frac{10001}{1000}=10.001$
[Power of 10 in denominator is 3, so move decimal point 3 places to the left]

$\frac{100001}{10000}=10.0001$
[Power of 10 in denominator is 4, so move decimal point 4 places to the left]

$\therefore 10.1+\frac{1001}{100}+\frac{10001}{1000}+\frac{100001}{10000}=10.1+10.01+10.001+10.0001$

The decimal point of numbers should be aligned for addition. Zeroes can be added to the front or back of the numbers to align the decimal point.

$\begin{array}{c}10.1000\\ +10.0100\\ +10.0010\\ \underset{–}{+10.0001}\\ \underset{–}{40.1111}\end{array}$