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Finding the Fourth Proportional to 387.43, 580.78 and 130.75

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Solution

The fourth proportional to 387.43, 580.78 and 130.75 is: 196.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.43 : 580.78 = 130.75 : x
  2. Step 2: Convert to fraction form
    387.43/580.78 = 130.75/x
  3. Step 3: Cross multiply
    387.43x = 580.78 × 130.75
  4. Step 4: Simplify right side
    387.43x = 75,936.99
  5. Step 5: Solve for x
    x = 75,936.99/387.43
  6. Step 6: Final answer
    x = 196.00

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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.