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Finding the Fourth Proportional to 420.47, 630.71 and 127.97

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Solution

The fourth proportional to 420.47, 630.71 and 127.97 is: 191.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.47 : 630.71 = 127.97 : x
  2. Step 2: Convert to fraction form
    420.47/630.71 = 127.97/x
  3. Step 3: Cross multiply
    420.47x = 630.71 × 127.97
  4. Step 4: Simplify right side
    420.47x = 80,714.48
  5. Step 5: Solve for x
    x = 80,714.48/420.47
  6. Step 6: Final answer
    x = 191.96

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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.