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Finding the Fourth Proportional to 651.20, 898.76 and 389.39

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Solution

The fourth proportional to 651.20, 898.76 and 389.39 is: 537.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    651.20 : 898.76 = 389.39 : x
  2. Step 2: Convert to fraction form
    651.20/898.76 = 389.39/x
  3. Step 3: Cross multiply
    651.20x = 898.76 × 389.39
  4. Step 4: Simplify right side
    651.20x = 349,964.64
  5. Step 5: Solve for x
    x = 349,964.64/651.20
  6. Step 6: Final answer
    x = 537.42

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.