All Exams Test series for 1 year @ ₹349 only
Question

The sum of binary numbers 1100100 and 101110 is ____.

This question was previously asked in
RRB ALP 2018 CBT 2 Fitter Question Paper (21-Jan-2019) (Shift 3)
The correct answer is

10010010

Understanding Binary Addition

Binary addition is a fundamental operation in digital electronics and computer systems. Unlike decimal addition which uses base 10, binary addition uses base 2. The rules for binary addition are simple:

  • \(0 + 0 = 0\) (with no carry)
  • \(0 + 1 = 1\) (with no carry)
  • \(1 + 0 = 1\) (with no carry)
  • \(1 + 1 = 0\) (with a carry of 1 to the next higher position)
  • \(1 + 1 + 1 = 1\) (with a carry of 1 to the next higher position)

When adding two binary numbers, we align them by their rightmost digit and add column by column, propagating any carries to the left, just like in decimal addition.

Let's find the sum of the given binary numbers: 1100100 and 101110.

Step-by-Step Binary Addition of 1100100 and 101110

To add 1100100 and 101110, we can align the numbers and add column by column from right to left.

Position (from right) 7 6 5 4 3 2 1
First Number: 1100100 1 1 0 0 1 0 0
Second Number: 101110 (padded) 0 1 0 1 1 1 0
Carry from right 1 0 1 1 0 0
Sum (current column) 0 0 1 0 1 0
Carry to left 1 0 0 1 1 0 0

Let's perform the addition column by column:

  • Rightmost column (Position 1): \(0 + 0 = 0\). Carry = 0. Result digit = 0.
  • Position 2: \(0 + 1 = 1\). Carry = 0. Result digit = 1.
  • Position 3: \(1 + 1 = 0\). Carry = 1. Result digit = 0.
  • Position 4: \(0 + 1 + \text{carry (1)} = 1 + 1 = 0\). Carry = 1. Result digit = 0.
  • Position 5: \(0 + 0 + \text{carry (1)} = 0 + 1 = 1\). Carry = 0. Result digit = 1.
  • Position 6: \(1 + 1 + \text{carry (0)} = 1 + 1 = 0\). Carry = 1. Result digit = 0.
  • Position 7: \(1 + 0 + \text{carry (1)} = 1 + 1 = 0\). Carry = 1. Result digit = 0.
  • Final Carry: The carry from Position 7 is 1, which becomes the leftmost digit of the sum. Result digit = 1.

Reading the resulting digits from left to right (including the final carry), we get 10010010.

Final Sum of Binary Numbers

The sum of the binary numbers 1100100 and 101110 is 10010010.

This matches one of the provided options.

Revision Table: Key Binary Addition Rules

Operation Sum Carry
\(0 + 0\) 0 0
\(0 + 1\) 1 0
\(1 + 0\) 1 0
\(1 + 1\) 0 1
\(1 + 1 + 1\) 1 1

Additional Information on Binary Numbers

Binary numbers are the foundation of digital computing. A binary digit (bit) can only be 0 or 1. Larger binary numbers represent values using powers of 2, similar to how decimal numbers use powers of 10. Understanding binary arithmetic, including binary addition, subtraction, multiplication, and division, is crucial for studying computer architecture, digital logic design, and low-level programming.

For instance, converting binary numbers to decimal can help verify the addition:

  • \(1100100_2 = 1 \times 2^6 + 1 \times 2^5 + 0 \times 2^4 + 0 \times 2^3 + 1 \times 2^2 + 0 \times 2^1 + 0 \times 2^0\)
  • \(1100100_2 = 64 + 32 + 0 + 0 + 4 + 0 + 0 = 100_{10}\)
  • \(101110_2 = 1 \times 2^5 + 0 \times 2^4 + 1 \times 2^3 + 1 \times 2^2 + 1 \times 2^1 + 0 \times 2^0\)
  • \(101110_2 = 32 + 0 + 8 + 4 + 2 + 0 = 46_{10}\)

Their decimal sum is \(100 + 46 = 146_{10}\).

Let's convert the binary sum 10010010 to decimal:

  • \(10010010_2 = 1 \times 2^7 + 0 \times 2^6 + 0 \times 2^5 + 1 \times 2^4 + 0 \times 2^3 + 0 \times 2^2 + 1 \times 2^1 + 0 \times 2^0\)
  • \(10010010_2 = 128 + 0 + 0 + 16 + 0 + 0 + 2 + 0 = 146_{10}\)

The decimal sum matches the decimal conversion of the binary sum, confirming the correctness of the binary addition.

Was this answer helpful?

Important Questions from Binary Operations

  1. Multiplication of 111 2by 101 2is

  2. Let * be binary operation defined on R by \(\rm p * q=\frac{p+q}{2}, \forall \) p, q ∈ R. The operation is:

  3. Convert 29 into binary.

    A. 10101

    B. 11110

    C. 11101

    D. 11001

  4. The product of the two binary numbers 011 and 110 is:

  5. If G is the set of integer numbers, and a.b = a – b, ∀ a, b ∈ G, then G is

Need Expert Advice?
Upcoming Exams
RRB NTPC
September 27, 2026
Test Series
RRB ALP img
Railways
RRB ALP 2026 Mock Test series
1035 Tests 1 Tests Free
917 Attempts
4.3(236)
English, Hindi

Start Your Preparation with Prepp Mobile App

Download the app from Google Play & App Store
Download the app from Google Play & App Store
Prepp Mobile App