Problem 5 - Algebra 1

Question

Rewrite in decimal form. $$ 8.11 \times 10^{3} $$

Step-by-Step Solution

Answer

The decimal form of \(8.11 \times 10^{3}\) is 8110.

Step 1: Understand the Power of 10

Firstly, the number after the power of 10, denoted as 3 in this case, indicates the number of places to move the decimal point in the stated number, here being 8.11.

Step 2: Move the Decimal Point

As the power of 10 is positive, the decimal point in the number 8.11 is moved 3 places to the right. When there are no more digits in the number, zeros are added.

Step 3: Write the Final Answer

The decimal point has been moved to its new position after having shifted 3 places to the right, and the final number is written as a decimal.

Key Concepts

Powers of Ten

Powers of ten are a fundamental concept in mathematics that help make large or small numbers more understandable. The expression \(10^n\) determines how many times the number 10 is multiplied by itself. When the exponent, denoted by \(n\), is a positive integer, such as in \(10^3\), it means multiplying ten by itself three times: \(10 \times 10 \times 10 = 1000\). This concept allows expressing large numbers succinctly. For example, \(8.11 \times 10^3\) represents 8.11 shifted three decimal places to the right, resulting in 8110.Conversely, if the exponent is negative, such as \(10^{-3}\), it implies division, or equivalently, multiplying by 0.001. Powers of ten are crucial in scientific notation, where they provide a compact way to specify scaled numbers up or down.

Decimal Conversion

Converting numbers from scientific notation to decimal form is straightforward with an understanding of powers of ten. Firstly, identify the power of ten's exponent to ascertain the movement of the decimal point. In our example, \(8.11 \times 10^3\), the exponent is 3. This positive value indicates moving the decimal point three places to the right.

• If the decimal point moves beyond the original digits, add zeroes.
• For a smaller exponent, imagine shifting left.

Thus, 8.11 becomes 8110. Remember, positive exponents move the point right, expanding the number, and negative exponents shift it left, compressing the original value.

Place Value

Place value forms the backbone of understanding number systems, especially when working with decimals. Each digit's position within a number determines its value. For example, in the number 8110:

• 8 is in the 'thousands' place, representing \(8 \times 1000 = 8000\).
• 1 is in the 'hundreds' place, indicating \(1 \times 100 = 100\).
• The second 1 is in the 'tens' place, adding \(1 \times 10 = 10\).
• Finally, 0 in the 'units' place sums to \(0 \times 1 = 0\).

When converting from scientific notation to decimal form, understanding place value ensures that any shifts in the decimal are correctly interpreted. It is the reason additional zeros are justified when the decimal has to move beyond existing digits, preserving the numerical value originally expressed.