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Finding the Fourth Proportional to 666.09, 999.54 and 392.85

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Solution

The fourth proportional to 666.09, 999.54 and 392.85 is: 589.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.09 : 999.54 = 392.85 : x
  2. Step 2: Convert to fraction form
    666.09/999.54 = 392.85/x
  3. Step 3: Cross multiply
    666.09x = 999.54 × 392.85
  4. Step 4: Simplify right side
    666.09x = 392,669.29
  5. Step 5: Solve for x
    x = 392,669.29/666.09
  6. Step 6: Final answer
    x = 589.51

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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.