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Finding the Fourth Proportional to 645.30, 890.46 and 383.28

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Solution

The fourth proportional to 645.30, 890.46 and 383.28 is: 528.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.30 : 890.46 = 383.28 : x
  2. Step 2: Convert to fraction form
    645.30/890.46 = 383.28/x
  3. Step 3: Cross multiply
    645.30x = 890.46 × 383.28
  4. Step 4: Simplify right side
    645.30x = 341,295.51
  5. Step 5: Solve for x
    x = 341,295.51/645.30
  6. Step 6: Final answer
    x = 528.89

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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.