Question 323 of 480
What is the decimal equivalent of the binary number 101101?
Correct Answer:
A
Explanation
To find the decimal equivalent of the binary number 101101, we will follow a step-by-step process to convert it from binary (base 2) to decimal (base 10).
### Step-by-Step Explanation
1. **Understanding Binary Numbers**:
- Binary numbers are composed of only two digits: 0 and 1. Each digit represents a power of 2, starting from the rightmost digit, which represents \(2^0\), the next one to the left represents \(2^1\), and so on.
2. **Identifying the Binary Number**:
- The binary number given is 101101. We will break it down from right to left:
- The rightmost digit (1) is in the \(2^0\) place.
- The next digit (0) is in the \(2^1\) place.
- The next digit (1) is in the \(2^2\) place.
- The next digit (1) is in the \(2^3\) place.
- The next digit (0) is in the \(2^4\) place.
- The leftmost digit (1) is in the \(2^5\) place.
3. **Calculating the Decimal Value**:
- Now, we will calculate the decimal value by multiplying each binary digit by its corresponding power of 2 and then summing the results:
\[
\text{Decimal Value} = (1 \times 2^5) + (0 \times 2^4) + (1 \times 2^3) + (1 \times 2^2) + (0 \times 2^1) + (1 \times 2^0)
\]
- Breaking it down:
- \(1 \times 2^5 = 1 \times 32 = 32\)
- \(0 \times 2^4 = 0 \times 16 = 0\)
- \(1 \times 2^3 = 1 \times 8 = 8\)
- \(1 \times 2^2 = 1 \times 4 = 4\)
- \(0 \times 2^1 = 0 \times 2 = 0\)
- \(1 \times 2^0 = 1 \times 1 = 1\)
- Now, we sum these values:
\[
32 + 0 + 8 + 4 + 0 + 1 = 45
\]
4. **Final Answer**:
- Therefore, the decimal equivalent of the binary number 101101 is **45**.
### Explanation of Other Options
- **Option B (22)**:
- This is incorrect because the calculations show that the total is 45, not 22.
- **Option C (37)**:
- This is also incorrect. The binary to decimal conversion does not yield 37 based on the calculations we performed.
- **Option D (23)**:
- This option is incorrect as well. The correct conversion gives us 45, not 23.
### Common Pitfalls
- **Miscounting Powers of 2**: Ensure you start counting from \(2^0\) on the rightmost side.
- **Forgetting to Add All Values**: Itβs easy to miss adding one of the calculated values, so double-check your addition.
- **Confusing Binary with Decimal**: Remember that binary only uses 0s and 1s, and each position represents a power of 2.
### Revision Summary
- Binary numbers are converted to decimal by multiplying each digit by its corresponding power of 2.
- The binary number 101101 converts to decimal as follows: \(1 \times 32 + 0 \times 16 + 1 \times 8 + 1 \times 4 + 0 \times 2 + 1 \times 1 = 45\).
- The correct answer is **A. 45**.
- Always check your calculations and ensure you understand the binary to decimal conversion process.