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Finding the Fourth Proportional to 101.53, 139.83 and 87.71

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Solution

The fourth proportional to 101.53, 139.83 and 87.71 is: 120.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    101.53 : 139.83 = 87.71 : x
  2. Step 2: Convert to fraction form
    101.53/139.83 = 87.71/x
  3. Step 3: Cross multiply
    101.53x = 139.83 × 87.71
  4. Step 4: Simplify right side
    101.53x = 12,264.49
  5. Step 5: Solve for x
    x = 12,264.49/101.53
  6. Step 6: Final answer
    x = 120.80

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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.