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Finding the Fourth Proportional to 645.92, 891.32 and 383.93

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Solution

The fourth proportional to 645.92, 891.32 and 383.93 is: 529.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.92 : 891.32 = 383.93 : x
  2. Step 2: Convert to fraction form
    645.92/891.32 = 383.93/x
  3. Step 3: Cross multiply
    645.92x = 891.32 × 383.93
  4. Step 4: Simplify right side
    645.92x = 342,201.45
  5. Step 5: Solve for x
    x = 342,201.45/645.92
  6. Step 6: Final answer
    x = 529.79

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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.