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Finding the Fourth Proportional to 137.80, 190.12 and 102.72

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Solution

The fourth proportional to 137.80, 190.12 and 102.72 is: 141.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    137.80 : 190.12 = 102.72 : x
  2. Step 2: Convert to fraction form
    137.80/190.12 = 102.72/x
  3. Step 3: Cross multiply
    137.80x = 190.12 × 102.72
  4. Step 4: Simplify right side
    137.80x = 19,529.13
  5. Step 5: Solve for x
    x = 19,529.13/137.80
  6. Step 6: Final answer
    x = 141.72

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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.