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Finding the Fourth Proportional to 137.70, 189.81 and 102.87

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Solution

The fourth proportional to 137.70, 189.81 and 102.87 is: 141.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    137.70 : 189.81 = 102.87 : x
  2. Step 2: Convert to fraction form
    137.70/189.81 = 102.87/x
  3. Step 3: Cross multiply
    137.70x = 189.81 × 102.87
  4. Step 4: Simplify right side
    137.70x = 19,525.75
  5. Step 5: Solve for x
    x = 19,525.75/137.70
  6. Step 6: Final answer
    x = 141.80

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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.