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Finding the Fourth Proportional to 137.20, 188.98 and 100.28

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Solution

The fourth proportional to 137.20, 188.98 and 100.28 is: 138.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    137.20 : 188.98 = 100.28 : x
  2. Step 2: Convert to fraction form
    137.20/188.98 = 100.28/x
  3. Step 3: Cross multiply
    137.20x = 188.98 × 100.28
  4. Step 4: Simplify right side
    137.20x = 18,950.91
  5. Step 5: Solve for x
    x = 18,950.91/137.20
  6. Step 6: Final answer
    x = 138.13

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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.