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Finding the Fourth Proportional to 645.14, 890.34 and 383.18

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Solution

The fourth proportional to 645.14, 890.34 and 383.18 is: 528.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.14 : 890.34 = 383.18 : x
  2. Step 2: Convert to fraction form
    645.14/890.34 = 383.18/x
  3. Step 3: Cross multiply
    645.14x = 890.34 × 383.18
  4. Step 4: Simplify right side
    645.14x = 341,160.48
  5. Step 5: Solve for x
    x = 341,160.48/645.14
  6. Step 6: Final answer
    x = 528.82

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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.