In place value notation, what is the numerical value of 28 tens?

Introduction / Context:
Place value is a core concept in the number system. It tells us how the position of a digit in a number determines its value in terms of ones, tens, hundreds and so on. Understanding statements such as 28 tens or 9 tens is important for interpreting numbers correctly in arithmetic reasoning questions.

Given Data / Assumptions:
- We are given the expression 28 tens.
- One ten is equal to 10 units (or 10 ones).
- We need to convert 28 tens into its equivalent numerical value in simple digits.

Concept / Approach:
The phrase 28 tens means 28 groups of 10. Therefore, the total value is 28 multiplied by 10. In place value terms, a digit in the tens place is worth 10 times its face value. Here we treat 28 as the count of tens and convert this into units by multiplication.

Step-by-Step Solution:
Step 1: Understand that 1 ten = 10 units. Step 2: Therefore, 28 tens = 28 * 10 units. Step 3: Multiply 28 by 10: 28 * 10 = 280. Step 4: Hence, the numerical value of 28 tens is 280.

Verification / Alternative Check:
You can think in terms of place value in a number like 280. The digit 8 is in the tens place and contributes 8 * 10 = 80, and the digit 2 in the hundreds place contributes 2 * 100 = 200, for a total of 280. Another way is to imagine writing 28 as 20 + 8 and then calculating 10 * 28 to verify that the answer is 280.

Why Other Options Are Wrong:
Option A (28) ignores the place value of tens and treats tens as ones.
Option B (2) is far too small and does not correspond to 28 groups of anything.
Option C (2800) comes from mistakenly multiplying by 100 instead of 10.

Common Pitfalls:
A common error is to confuse tens and hundreds, leading to multiplication by 100 instead of 10. Some learners also misread 28 tens as simply the number 28 rather than a count of tens. Carefully translating verbal place value statements into multiplication helps avoid these mistakes.

Final Answer:
The value of 28 tens is 280.