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Finding the Fourth Proportional to 130.92, 180.68 and 78.47

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Solution

The fourth proportional to 130.92, 180.68 and 78.47 is: 108.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    130.92 : 180.68 = 78.47 : x
  2. Step 2: Convert to fraction form
    130.92/180.68 = 78.47/x
  3. Step 3: Cross multiply
    130.92x = 180.68 × 78.47
  4. Step 4: Simplify right side
    130.92x = 14,176.66
  5. Step 5: Solve for x
    x = 14,176.66/130.92
  6. Step 6: Final answer
    x = 108.28

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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.