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Finding the Fourth Proportional to 487.30, 671.96 and 398.12

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Solution

The fourth proportional to 487.30, 671.96 and 398.12 is: 548.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    487.30 : 671.96 = 398.12 : x
  2. Step 2: Convert to fraction form
    487.30/671.96 = 398.12/x
  3. Step 3: Cross multiply
    487.30x = 671.96 × 398.12
  4. Step 4: Simplify right side
    487.30x = 267,516.11
  5. Step 5: Solve for x
    x = 267,516.11/487.30
  6. Step 6: Final answer
    x = 548.98

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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.