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Finding the Fourth Proportional to 71.63, 98.85 and 38.89

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Solution

The fourth proportional to 71.63, 98.85 and 38.89 is: 53.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.63 : 98.85 = 38.89 : x
  2. Step 2: Convert to fraction form
    71.63/98.85 = 38.89/x
  3. Step 3: Cross multiply
    71.63x = 98.85 × 38.89
  4. Step 4: Simplify right side
    71.63x = 3,843.88
  5. Step 5: Solve for x
    x = 3,843.88/71.63
  6. Step 6: Final answer
    x = 53.66

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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.