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Finding the Fourth Proportional to 101.29, 139.57 and 86.49

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Solution

The fourth proportional to 101.29, 139.57 and 86.49 is: 119.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    101.29 : 139.57 = 86.49 : x
  2. Step 2: Convert to fraction form
    101.29/139.57 = 86.49/x
  3. Step 3: Cross multiply
    101.29x = 139.57 × 86.49
  4. Step 4: Simplify right side
    101.29x = 12,071.41
  5. Step 5: Solve for x
    x = 12,071.41/101.29
  6. Step 6: Final answer
    x = 119.18

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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.