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Cross multiplication is a handy technique used to solve equations involving fractions. It allows us to eliminate the fractions and simplify the equation. For the problem given, cross multiplication involves rearranging the equation \( \frac{1.2}{2.8} = \frac{n}{32} \). Here, the fractions can be removed by multiplying the numerator of one fraction by the denominator of the opposite fraction, and vice versa. This technique simplifies our equation to \( 1.2 \times 32 = 2.8 \times n \). By doing so, we can solve for \( n \) more easily, without any fractions to deal with. Cross multiplication is especially helpful in these types of rational equations because it directly isolates the variable.

Understanding decimal division is crucial when working with equations that include decimals, like \( \frac{1.2}{2.8} \). Dividing decimals may seem complex at first, but it's simpler when you break it down. To divide decimals:

• First, move the decimal point in the divisor (2.8) to the right to make it a whole number (28).
• Next, do the same with the dividend (1.2), moving the decimal one place to the right to make it 12.
• Now you can perform the division as if dividing by whole numbers: 12 divided by 28.
• Finally, place the decimal point in the quotient directly above where it appears in the dividend.

This understanding helps you solve the equation accurately by building confidence in dealing with decimal numbers.

Once you have your decimal result after solving the equation, rounding it to the nearest hundredth becomes important. The nearest hundredth refers to the second decimal place from the right in a number. If you end up with a result like 13.714, you'll need to consider the third decimal place to round correctly:

• If the third decimal is five or more, round the second decimal up. So, 13.714 rounds to 13.71.
• If it's less than five, keep the second decimal as is. For example, 13.723 rounds to 13.72.

Rounding helps in making your final answer fit the precise format required by the problem, ensuring your answer isn't unnecessarily lengthy or difficult to read.

Prealgebra serves as the foundation for solving equations like the one presented. It involves understanding basic mathematical operations and properties, all essential for grasping more complex mathematical ideas. In this problem, prealgebra concepts guide you in:

• Recognizing how multiplication and division can help isolate variables.
• Utilizing properties of fractions and decimals to simplify calculations.
• Applying basic arithmetic to manage numeric operations efficiently.

Grasping these concepts allows students to build confidence and fluency in mathematical problem-solving, paving the way for success as they move on to more advanced topics. Mastery of prealgebra ensures a strong math foundation and prepares students for more complex equations and algebra.