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Finding the Fourth Proportional to 666.48, 999.28 and 392.40

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Solution

The fourth proportional to 666.48, 999.28 and 392.40 is: 588.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.48 : 999.28 = 392.40 : x
  2. Step 2: Convert to fraction form
    666.48/999.28 = 392.40/x
  3. Step 3: Cross multiply
    666.48x = 999.28 × 392.40
  4. Step 4: Simplify right side
    666.48x = 392,117.47
  5. Step 5: Solve for x
    x = 392,117.47/666.48
  6. Step 6: Final answer
    x = 588.34

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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.