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Finding the Fourth Proportional to 130.20, 178.86 and 122.10

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Solution

The fourth proportional to 130.20, 178.86 and 122.10 is: 167.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    130.20 : 178.86 = 122.10 : x
  2. Step 2: Convert to fraction form
    130.20/178.86 = 122.10/x
  3. Step 3: Cross multiply
    130.20x = 178.86 × 122.10
  4. Step 4: Simplify right side
    130.20x = 21,838.81
  5. Step 5: Solve for x
    x = 21,838.81/130.20
  6. Step 6: Final answer
    x = 167.73

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.