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Finding the Fourth Proportional to 101.34, 139.77 and 71.87

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Solution

The fourth proportional to 101.34, 139.77 and 71.87 is: 99.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    101.34 : 139.77 = 71.87 : x
  2. Step 2: Convert to fraction form
    101.34/139.77 = 71.87/x
  3. Step 3: Cross multiply
    101.34x = 139.77 × 71.87
  4. Step 4: Simplify right side
    101.34x = 10,044.57
  5. Step 5: Solve for x
    x = 10,044.57/101.34
  6. Step 6: Final answer
    x = 99.12

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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.