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Finding the Fourth Proportional to 638.68, 881.06 and 428.59

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Solution

The fourth proportional to 638.68, 881.06 and 428.59 is: 591.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.68 : 881.06 = 428.59 : x
  2. Step 2: Convert to fraction form
    638.68/881.06 = 428.59/x
  3. Step 3: Cross multiply
    638.68x = 881.06 × 428.59
  4. Step 4: Simplify right side
    638.68x = 377,609.10
  5. Step 5: Solve for x
    x = 377,609.10/638.68
  6. Step 6: Final answer
    x = 591.23

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.