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Finding the Fourth Proportional to 645.14, 890.31 and 383.36

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Solution

The fourth proportional to 645.14, 890.31 and 383.36 is: 529.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.14 : 890.31 = 383.36 : x
  2. Step 2: Convert to fraction form
    645.14/890.31 = 383.36/x
  3. Step 3: Cross multiply
    645.14x = 890.31 × 383.36
  4. Step 4: Simplify right side
    645.14x = 341,309.24
  5. Step 5: Solve for x
    x = 341,309.24/645.14
  6. Step 6: Final answer
    x = 529.05

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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.