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Finding the Fourth Proportional to 387.00, 580.76 and 213.80

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Solution

The fourth proportional to 387.00, 580.76 and 213.80 is: 320.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.00 : 580.76 = 213.80 : x
  2. Step 2: Convert to fraction form
    387.00/580.76 = 213.80/x
  3. Step 3: Cross multiply
    387.00x = 580.76 × 213.80
  4. Step 4: Simplify right side
    387.00x = 124,165.57
  5. Step 5: Solve for x
    x = 124,165.57/387.00
  6. Step 6: Final answer
    x = 320.84

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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.