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Finding the Fourth Proportional to 819.84, 1,230 and 409.32

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Solution

The fourth proportional to 819.84, 1,230 and 409.32 is: 614.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    819.84 : 1,230 = 409.32 : x
  2. Step 2: Convert to fraction form
    819.84/1,230 = 409.32/x
  3. Step 3: Cross multiply
    819.84x = 1,230 × 409.32
  4. Step 4: Simplify right side
    819.84x = 503,463.60
  5. Step 5: Solve for x
    x = 503,463.60/819.84
  6. Step 6: Final answer
    x = 614.10

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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.