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Cross multiplication is a technique used to solve equations involving fractions where both sides have a fraction. You can cross multiply to get rid of the denominators and turn the equation into a simpler one.
To cross multiply, multiply the numerator of the first fraction by the denominator of the second fraction, and vice versa. Here's how it works with our example equation \(\frac{924}{x}=\frac{132}{100} \):
- Multiply 924 (numerator on the left) by 100 (denominator on the right): 924 \times 100
- Multiply 132 (numerator on the right) by x (denominator on the left): 132 \times x
Then, set these two products equal to each other: \[ 924 \times 100 = 132 \times x \]
Once done, you will have a basic algebraic equation you can solve easily by isolating \(x\).

Simplifying fractions means finding a simpler fraction that is equal to the original one. This process makes calculations easier and is very useful in solving equations.
To simplify, divide both the numerator and the denominator by their greatest common divisor (GCD). For instance, in the fraction \(\frac{132}{100}\), the GCD of 132 and 100 is 4.
Here's the step-by-step simplification:

• Divide the numerator by 4: 132 ÷ 4 = 33
• Divide the denominator by 4: 100 ÷ 4 = 25

So, \(\frac{132}{100} = \frac{33}{25}\).
This makes the equation easier to handle. Don't forget to check that you'll end up with smaller and more manageable numbers.

To isolate a variable means to get the variable on one side of the equation by itself. This allows you to solve for its value.
In our example, once we've cross-multiplied, we have the equation: \(23100 = 33x\).
You need to isolate \(x\). Do this by dividing both sides by 33:

• \begin{align*}23100 \div 33 = x \end{align*}

This gives:

• Super simple! This technique can be used on any equation to find the unknown variable.

The isolated variable tells you the solution to the problem.