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Finding the Fourth Proportional to 618.87, 928.31 and 228.90

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Solution

The fourth proportional to 618.87, 928.31 and 228.90 is: 343.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    618.87 : 928.31 = 228.90 : x
  2. Step 2: Convert to fraction form
    618.87/928.31 = 228.90/x
  3. Step 3: Cross multiply
    618.87x = 928.31 × 228.90
  4. Step 4: Simplify right side
    618.87x = 212,491.17
  5. Step 5: Solve for x
    x = 212,491.17/618.87
  6. Step 6: Final answer
    x = 343.36

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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.