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Finding the Fourth Proportional to 638.79, 962.20 and 581.38

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Solution

The fourth proportional to 638.79, 962.20 and 581.38 is: 875.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.79 : 962.20 = 581.38 : x
  2. Step 2: Convert to fraction form
    638.79/962.20 = 581.38/x
  3. Step 3: Cross multiply
    638.79x = 962.20 × 581.38
  4. Step 4: Simplify right side
    638.79x = 559,403.84
  5. Step 5: Solve for x
    x = 559,403.84/638.79
  6. Step 6: Final answer
    x = 875.72

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.