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Finding the Fourth Proportional to 645.27, 890.70 and 383.28

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Solution

The fourth proportional to 645.27, 890.70 and 383.28 is: 529.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.27 : 890.70 = 383.28 : x
  2. Step 2: Convert to fraction form
    645.27/890.70 = 383.28/x
  3. Step 3: Cross multiply
    645.27x = 890.70 × 383.28
  4. Step 4: Simplify right side
    645.27x = 341,388.76
  5. Step 5: Solve for x
    x = 341,388.76/645.27
  6. Step 6: Final answer
    x = 529.07

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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.