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Finding the Fourth Proportional to 480.64, 720.28 and 285.69

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Solution

The fourth proportional to 480.64, 720.28 and 285.69 is: 428.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    480.64 : 720.28 = 285.69 : x
  2. Step 2: Convert to fraction form
    480.64/720.28 = 285.69/x
  3. Step 3: Cross multiply
    480.64x = 720.28 × 285.69
  4. Step 4: Simplify right side
    480.64x = 205,776.79
  5. Step 5: Solve for x
    x = 205,776.79/480.64
  6. Step 6: Final answer
    x = 428.13

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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.