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Finding the Fourth Proportional to 387.03, 581.12 and 309.75

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Solution

The fourth proportional to 387.03, 581.12 and 309.75 is: 465.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.03 : 581.12 = 309.75 : x
  2. Step 2: Convert to fraction form
    387.03/581.12 = 309.75/x
  3. Step 3: Cross multiply
    387.03x = 581.12 × 309.75
  4. Step 4: Simplify right side
    387.03x = 180,001.92
  5. Step 5: Solve for x
    x = 180,001.92/387.03
  6. Step 6: Final answer
    x = 465.09

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.