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Finding the Fourth Proportional to 130.54, 180.15 and 78.10

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Solution

The fourth proportional to 130.54, 180.15 and 78.10 is: 107.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    130.54 : 180.15 = 78.10 : x
  2. Step 2: Convert to fraction form
    130.54/180.15 = 78.10/x
  3. Step 3: Cross multiply
    130.54x = 180.15 × 78.10
  4. Step 4: Simplify right side
    130.54x = 14,069.72
  5. Step 5: Solve for x
    x = 14,069.72/130.54
  6. Step 6: Final answer
    x = 107.78

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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.