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Finding the Fourth Proportional to 101.03, 139.14 and 87.21

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Solution

The fourth proportional to 101.03, 139.14 and 87.21 is: 120.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    101.03 : 139.14 = 87.21 : x
  2. Step 2: Convert to fraction form
    101.03/139.14 = 87.21/x
  3. Step 3: Cross multiply
    101.03x = 139.14 × 87.21
  4. Step 4: Simplify right side
    101.03x = 12,134.40
  5. Step 5: Solve for x
    x = 12,134.40/101.03
  6. Step 6: Final answer
    x = 120.11

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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.