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Finding the Fourth Proportional to 651.28, 898.78 and 389.42

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Solution

The fourth proportional to 651.28, 898.78 and 389.42 is: 537.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    651.28 : 898.78 = 389.42 : x
  2. Step 2: Convert to fraction form
    651.28/898.78 = 389.42/x
  3. Step 3: Cross multiply
    651.28x = 898.78 × 389.42
  4. Step 4: Simplify right side
    651.28x = 350,002.91
  5. Step 5: Solve for x
    x = 350,002.91/651.28
  6. Step 6: Final answer
    x = 537.41

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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.