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Finding the Fourth Proportional to 638.64, 880.50 and 520.20

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Solution

The fourth proportional to 638.64, 880.50 and 520.20 is: 717.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.64 : 880.50 = 520.20 : x
  2. Step 2: Convert to fraction form
    638.64/880.50 = 520.20/x
  3. Step 3: Cross multiply
    638.64x = 880.50 × 520.20
  4. Step 4: Simplify right side
    638.64x = 458,036.10
  5. Step 5: Solve for x
    x = 458,036.10/638.64
  6. Step 6: Final answer
    x = 717.21

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.