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Finding the Fourth Proportional to 487.47, 731.21 and 198.91

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Solution

The fourth proportional to 487.47, 731.21 and 198.91 is: 298.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    487.47 : 731.21 = 198.91 : x
  2. Step 2: Convert to fraction form
    487.47/731.21 = 198.91/x
  3. Step 3: Cross multiply
    487.47x = 731.21 × 198.91
  4. Step 4: Simplify right side
    487.47x = 145,444.98
  5. Step 5: Solve for x
    x = 145,444.98/487.47
  6. Step 6: Final answer
    x = 298.37

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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.