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Finding the Fourth Proportional to 71.72, 99.07 and 55.55

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Solution

The fourth proportional to 71.72, 99.07 and 55.55 is: 76.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.72 : 99.07 = 55.55 : x
  2. Step 2: Convert to fraction form
    71.72/99.07 = 55.55/x
  3. Step 3: Cross multiply
    71.72x = 99.07 × 55.55
  4. Step 4: Simplify right side
    71.72x = 5,502.57
  5. Step 5: Solve for x
    x = 5,502.57/71.72
  6. Step 6: Final answer
    x = 76.73

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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.