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Finding the Fourth Proportional to 645.28, 890.60 and 383.44

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Solution

The fourth proportional to 645.28, 890.60 and 383.44 is: 529.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.28 : 890.60 = 383.44 : x
  2. Step 2: Convert to fraction form
    645.28/890.60 = 383.44/x
  3. Step 3: Cross multiply
    645.28x = 890.60 × 383.44
  4. Step 4: Simplify right side
    645.28x = 341,491.66
  5. Step 5: Solve for x
    x = 341,491.66/645.28
  6. Step 6: Final answer
    x = 529.21

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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.