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Finding the Fourth Proportional to 512.80, 765.80 and 408.04

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Solution

The fourth proportional to 512.80, 765.80 and 408.04 is: 609.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    512.80 : 765.80 = 408.04 : x
  2. Step 2: Convert to fraction form
    512.80/765.80 = 408.04/x
  3. Step 3: Cross multiply
    512.80x = 765.80 × 408.04
  4. Step 4: Simplify right side
    512.80x = 312,477.03
  5. Step 5: Solve for x
    x = 312,477.03/512.80
  6. Step 6: Final answer
    x = 609.35

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.