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Finding the Fourth Proportional to 47.90, 66.10 and 30.39

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Solution

The fourth proportional to 47.90, 66.10 and 30.39 is: 41.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    47.90 : 66.10 = 30.39 : x
  2. Step 2: Convert to fraction form
    47.90/66.10 = 30.39/x
  3. Step 3: Cross multiply
    47.90x = 66.10 × 30.39
  4. Step 4: Simplify right side
    47.90x = 2,008.78
  5. Step 5: Solve for x
    x = 2,008.78/47.90
  6. Step 6: Final answer
    x = 41.94

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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.