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Finding the Fourth Proportional to 666.60, 999.57 and 392.79

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Solution

The fourth proportional to 666.60, 999.57 and 392.79 is: 588.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.60 : 999.57 = 392.79 : x
  2. Step 2: Convert to fraction form
    666.60/999.57 = 392.79/x
  3. Step 3: Cross multiply
    666.60x = 999.57 × 392.79
  4. Step 4: Simplify right side
    666.60x = 392,621.10
  5. Step 5: Solve for x
    x = 392,621.10/666.60
  6. Step 6: Final answer
    x = 588.99

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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.