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Finding the Fourth Proportional to 638.48, 958.20 and 511.76

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Solution

The fourth proportional to 638.48, 958.20 and 511.76 is: 768.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.48 : 958.20 = 511.76 : x
  2. Step 2: Convert to fraction form
    638.48/958.20 = 511.76/x
  3. Step 3: Cross multiply
    638.48x = 958.20 × 511.76
  4. Step 4: Simplify right side
    638.48x = 490,368.43
  5. Step 5: Solve for x
    x = 490,368.43/638.48
  6. Step 6: Final answer
    x = 768.02

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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.