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Finding the Fourth Proportional to 720.21, 1,080.24 and 330.09

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Solution

The fourth proportional to 720.21, 1,080.24 and 330.09 is: 495.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    720.21 : 1,080.24 = 330.09 : x
  2. Step 2: Convert to fraction form
    720.21/1,080.24 = 330.09/x
  3. Step 3: Cross multiply
    720.21x = 1,080.24 × 330.09
  4. Step 4: Simplify right side
    720.21x = 356,576.42
  5. Step 5: Solve for x
    x = 356,576.42/720.21
  6. Step 6: Final answer
    x = 495.10

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.