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Finding the Fourth Proportional to 642.28, 963.87 and 580.31

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Solution

The fourth proportional to 642.28, 963.87 and 580.31 is: 870.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.28 : 963.87 = 580.31 : x
  2. Step 2: Convert to fraction form
    642.28/963.87 = 580.31/x
  3. Step 3: Cross multiply
    642.28x = 963.87 × 580.31
  4. Step 4: Simplify right side
    642.28x = 559,345.81
  5. Step 5: Solve for x
    x = 559,345.81/642.28
  6. Step 6: Final answer
    x = 870.88

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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.