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Finding the Fourth Proportional to 71.01, 97.91 and 61.90

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Solution

The fourth proportional to 71.01, 97.91 and 61.90 is: 85.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.01 : 97.91 = 61.90 : x
  2. Step 2: Convert to fraction form
    71.01/97.91 = 61.90/x
  3. Step 3: Cross multiply
    71.01x = 97.91 × 61.90
  4. Step 4: Simplify right side
    71.01x = 6,060.31
  5. Step 5: Solve for x
    x = 6,060.31/71.01
  6. Step 6: Final answer
    x = 85.34

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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.