Solving a proportion by cross multiplication with decimals

The video tutorial demonstrates how to solve a proportion involving decimals using the cross product method. It begins with an introduction to proportions and explains the cross product technique. The instructor then provides a detailed, step-by-step solution to the equation 7 * 1.5 = y * 2.5, ultimately finding that y equals 4.2. The tutorial concludes with a summary of the solution process.

What is a proportion in mathematical terms?

• A sum of two numbers

• A comparison of two numbers by division

• A product of two numbers

• A difference of two numbers

What is the first step in solving a proportion using cross products?

• Multiply the numbers diagonally

• Divide the numbers

• Subtract the numbers

• Add the numbers

How do you calculate 7 * 1.5?

• 11.5

• 9.5

• 8.5

• 10.5

What operation is used to isolate y in the equation 10.5 = 2.5y?

• Division

• Subtraction

• Addition

• Multiplication

What is the value of y when 10.5 is divided by 2.5?

• 5.2

• 3.2

• 4.2

• 6.2