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Finding the Fourth Proportional to 651.85, 978.46 and 392.49

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Solution

The fourth proportional to 651.85, 978.46 and 392.49 is: 589.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    651.85 : 978.46 = 392.49 : x
  2. Step 2: Convert to fraction form
    651.85/978.46 = 392.49/x
  3. Step 3: Cross multiply
    651.85x = 978.46 × 392.49
  4. Step 4: Simplify right side
    651.85x = 384,035.77
  5. Step 5: Solve for x
    x = 384,035.77/651.85
  6. Step 6: Final answer
    x = 589.15

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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.