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Finding the Fourth Proportional to 426.30, 640.08 and 409.92

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Solution

The fourth proportional to 426.30, 640.08 and 409.92 is: 615.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    426.30 : 640.08 = 409.92 : x
  2. Step 2: Convert to fraction form
    426.30/640.08 = 409.92/x
  3. Step 3: Cross multiply
    426.30x = 640.08 × 409.92
  4. Step 4: Simplify right side
    426.30x = 262,381.59
  5. Step 5: Solve for x
    x = 262,381.59/426.30
  6. Step 6: Final answer
    x = 615.49

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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.