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Finding the Fourth Proportional to 39.71, 54.63 and 30.47

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Solution

The fourth proportional to 39.71, 54.63 and 30.47 is: 41.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    39.71 : 54.63 = 30.47 : x
  2. Step 2: Convert to fraction form
    39.71/54.63 = 30.47/x
  3. Step 3: Cross multiply
    39.71x = 54.63 × 30.47
  4. Step 4: Simplify right side
    39.71x = 1,664.30
  5. Step 5: Solve for x
    x = 1,664.30/39.71
  6. Step 6: Final answer
    x = 41.91

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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.