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Finding the Fourth Proportional to 101.34, 139.28 and 89.61

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Solution

The fourth proportional to 101.34, 139.28 and 89.61 is: 123.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    101.34 : 139.28 = 89.61 : x
  2. Step 2: Convert to fraction form
    101.34/139.28 = 89.61/x
  3. Step 3: Cross multiply
    101.34x = 139.28 × 89.61
  4. Step 4: Simplify right side
    101.34x = 12,480.88
  5. Step 5: Solve for x
    x = 12,480.88/101.34
  6. Step 6: Final answer
    x = 123.16

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.