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Finding the Fourth Proportional to 138.15, 190.48 and 130.20

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Solution

The fourth proportional to 138.15, 190.48 and 130.20 is: 179.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.15 : 190.48 = 130.20 : x
  2. Step 2: Convert to fraction form
    138.15/190.48 = 130.20/x
  3. Step 3: Cross multiply
    138.15x = 190.48 × 130.20
  4. Step 4: Simplify right side
    138.15x = 24,800.50
  5. Step 5: Solve for x
    x = 24,800.50/138.15
  6. Step 6: Final answer
    x = 179.52

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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.