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Finding the Fourth Proportional to 429.57, 640.85 and 409.05

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Solution

The fourth proportional to 429.57, 640.85 and 409.05 is: 610.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    429.57 : 640.85 = 409.05 : x
  2. Step 2: Convert to fraction form
    429.57/640.85 = 409.05/x
  3. Step 3: Cross multiply
    429.57x = 640.85 × 409.05
  4. Step 4: Simplify right side
    429.57x = 262,137.65
  5. Step 5: Solve for x
    x = 262,137.65/429.57
  6. Step 6: Final answer
    x = 610.23

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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.